Shaving Aid For Razor Cartridges Comprising A Nano-Filament Comprising A Core And Sheath

ABSTRACT

A shaving aid for razor cartridges comprising water soluble filaments having nano-sized diameters and exhibiting lubricating properties and with improved visual and tactile aesthetics, wherein said nano-filament has a core and a sheath.

FIELD OF THE INVENTION

The invention relates to a shaving aid for razor cartridges comprisingwater soluble filaments based shaving aid exhibiting lubricatingproperties and with improved visual and tactile aesthetics.

BACKGROUND OF THE INVENTION

The use of shaving aids on razor blades to provide lubrication benefitsduring the shave is known; see for example U.S. Pat. No. 7,121,754, U.S.Pat. No. 6,298,558, U.S. Pat. No. 5,711,076, U.S. Pat. No. 6,301,785,US2009/0223057 and US2006/0225285. Such shaving aids, typically calledLubrastrips, comprise a water-insoluble matrix material to providestructural integrity and a water-soluble polymer, such as polyethyleneoxide, in order to provide lubrication during the shave once thewater-soluble polymer forms a solution with the water present duringshaving. Since the introduction of Lubrastrips, little development hasbeen made in the field, even though these forms are not withoutlimitations. For example, the polyethylene oxide lubricant can beperceived negatively by the consumer due to its inherent stringiness,the form and manufacturing process can degrade the polyethylene oxideefficacy and limit the inclusion of skin care actives and Lubrastripsare a hard non-compliant form that does not provide an appealingsensation on the skin.

Consequently, there is still a need to provide a shaving aid for razorcartridges exhibiting lubricating properties with the ability to containand deliver a range of desirable skin actives in a controlled mannerover multiple usage events, whilst also providing a differentiated andappealing visual and tactile aesthetics before and during use.

Surprisingly, it has been found that the provision of water solublefilaments on a razor cartridge, in a shaving aid for example, canprovide these desired benefits. The filaments are preferably comprisedof water soluble materials which act as both filament forming materialsand lubricants whilst providing a desirable aesthetic before and duringuse. Optionally, the shaving aid may be coated or impregnated with skincare actives and/or laminated to further increase conformability and theperception of softness. Both the coating or impregnation and laminationalso have the additional desired effect of controlling the rate ofdissolution of the filaments and associated shaving aid in use.

Fibrous or filament forms are known for use on razor cartridges, asdescribed for example in WO2013/096178. The fibres are described asresilient and non-water soluble and comprise a hydrophobic non-wovenmaterial including a polyamide or polyester. The function of the fibresis merely to act as an applicator and reservoir for shaving fluiddispensed into or onto the fibrous pad rather than any for an additionalfunctional benefit. A problem with such resilient fibre or filament padshowever is that the pads are prone to forming an undesirable appearanceover use due to skin and hair debris collecting in the interstices.

The use of filament or fibrous substrates, often termed as non-wovensubstrates are described in consumer applications such as tissue toweland are characterized by a desirable cloth like feel and appearance. Forexample, US2013/0209272 describes a wet wipe comprising a non-wovensubstrate including polyvinylalcohol filaments or fibres and a surfacetreatment of hydrophilic material. Such webs can also be stacked orlayered as described in WO20090022761 which describes stacking ofdissolvable nano webs comprising fibres or filaments including starchand PVA. However, these webs have a high rate of dissolution and are notsuitable for multiple usage. The use of filament forming materials thatrelease actives in use are also described for example in US2012/0052036,US2012/0237576 and US2013/017142.

Very thin fibers have also been disclosed in other publications, seee.g., WO 2001026610, WO 2001051690, and U.S. Pat. No. 8,367,570 and U.S.Pat. No. 7,390,760. Despite these and other disclosures, there remains aneed for innovation on the shaving aid space as conventional shavingaids can be limited in the amount or type of lubrication they provideand there can be a need for meaningful skin benefits which have not beenoffered in other shaving aids on the market.

SUMMARY OF THE INVENTION

The present invention fulfills the need described above by providingnano-diameter sized filaments (“defined herein as nano-filaments”) whichare water soluble filaments for incorporation onto a razor cartridge forexample in or on the housing or in the form of a shaving aid for a razorcartridge. Also within the scope of the present invention is theaddition of larger filaments (referred to hereinafter as “filaments”)which can also be made of water soluble materials. The shaving aid mayemploy one or more layers of webs comprising nano-filaments and/orfilaments, said webs preferably provide a lubricating benefit but otherskin benefits can also be delivered depending on the components used toform the nano-filaments/filaments. The webs can also be selected andtexturized to provide desired visual and tactile aesthetics. Thenano-filament of this invention is co-axial wherein the filamentcomprises a core and sheath, wherein the materials forming the core areimmiscible with the material forming the sheath.

Methods of making such nano-filaments are also within the scope of thisinvention. One embodiment of the invention provides for a method ofmaking a shaving aid comprising: extruding a shaving aid through a dieto form an extruded shaving aid, said shaving aid having a skincontacting surface; and electrospinning at least two components to forma co-axial nano-filament onto a portion of the skin contacting surfaceto form a coated shaving aid, said two components being immiscible.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 to 4 depicts schematic cross sections of webs and laminatesexamples L1, L2, L3, 6, 6A, L6, L4 and L5 according to the invention.

FIG. 5 is a microscopic image of a nano-filament in accordance with atleast one embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION Definitions

“Filament” as used herein means an elongate particulate having a lengthgreatly exceeding its diameter, i.e. a length to diameter ratio of atleast about 5.

The filaments of the present invention may be spun from filament-formingcompositions via suitable spinning processes operations, such asmeltblowing, spun bonding and/or electro-spinning.

The filaments of the present invention may be monocomponent and/ormulticomponent. For example, the filaments may comprise bicomponentfilaments. The bicomponent or multicomponent filaments may be in anyform, such as side-by-side, core and sheath, islands-in-the-sea and thelike.

The filaments of the present invention may exhibit a length of greaterthan or equal to 5.08 cm (2 in.) and/or greater than or equal to 7.62 cm(3 in.) and/or greater than or equal to 10.16 cm (4 in.) and/or greaterthan or equal to 15.24 cm (6 in.). The filament length refers to thelength of the filaments after formation. However, in order to utilizethe filaments on the razor cartridge or shaving aid therefore, thefilaments or webs comprising the filaments may have a length less thanthe above values.

“Filament-forming composition” as used herein means a composition thatis suitable for making a filament of the present invention such as bymeltblowing, spunbonding and/or electro-spinning. The filament-formingcomposition comprises one or more filament-forming materials, preferablya lubricating filament forming material. The filament forming materialsexhibit properties that make them suitable for spinning into a filament.In addition to one or more filament-forming materials, thefilament-forming composition may optionally comprise one or moreadditives, for example one or more skin care active agents. In addition,the filament-forming composition may comprise one or more polarsolvents, such as water, into which one or more, for example all, of thefilament-forming materials and/or one or more, for example all, of theactive agents are dissolved and/or dispersed. The total level offilament-forming materials and total level of active agents present inthe filament-forming composition may be any suitable amount providedthat the filaments of the present invention are produced therefrom.

“Nano-filament” as used herein means a filament having a diameter ofless than or equal to 1000 nm. diameter of from about 10 nm to about1000 nm. The nano-filament comprises a diameter of from about 10 nm toabout 1000 nm, preferably from about 250 nm to about 750 nm, about 300nm to about 600 nm, or even about 350 to about 550 nm. Unless specifiedotherwise herein, nano-filaments can include the same components as usedto form filaments, and any descriptions of measurements regardingfilaments can also apply to nano-filaments unless the technique ordescription is specific to fibers having diameters larger than 1 μm.While the compositional make up of a nano-filament can be the same as afilament, nano-filaments can also be made up of different components andcan be made with more specific processing techniques. Those of skill inthe art will appreciate that “fibers” and “filaments” can be usedinterchangeably.

“Filament-forming material” as used herein means a polymer or monomers,preferably water soluble polymers or monomers capable of producing apolymer, which is suitable for making a filament.

“Filament-forming lubricating material” as used herein means a polymeror monomers, preferably water soluble polymer or monomer capable ofproducing a polymer, that exhibits lubricating properties and which aresuitable for making a filament.

“Additive” as used herein means any material present in the filament ofthe present invention that is not a filament-forming material. Anadditive may comprise a skin care active agent, a processing aid, afiller, a plasticizer, a cross-linking agent, a rheology modifier, acolourant, a release agent, a chelant and/or an anti-blocking ordetackifying agent. An additive comprises any material present in thefilament, that if absent from the filament, would not result in thefilament losing its filament structure, in other words, its absence doesnot result in the filament losing its solid form.

“Skin care active agent” as used herein, means an active agent that whenapplied to the skin provides a benefit or improvement to the skin. Thebenefit may be immediate or chronic in nature. It includes, but is notlimited to cleansing, sebum inhibition, increasing or reducing the oilyand/or shiny appearance of skin, reducing dryness and/or redness,itchiness and/or flakiness, reducing skin pore size, exfoliation,desquamation, improving the appearance of the skin tissue, conditioning,moisturizing, smoothening, perfuming, deodorizing skin, reducinginflammation, hair softening, depilatory and/or providing antiperspirantbenefits, etc.

“Conditions of intended use” as used herein means the temperature,physical, chemical, and/or mechanical conditions that the filament ofthe present invention is exposed to when used for its designed purposeof incorporation on a razor cartridge.

“Treatment” as used herein with respect to treating a surface includingskin means that the active agent provides a benefit to a surface orenvironment. Treatments include lubricating the skin, regulating and/orimmediately improving the skins cosmetic appearance, cleanliness, smell,and/or feel. In one example treatment in reference to treating skintissue means deposition of a occlusive skin moisturization agent duringthe shaving process.

“Weight ratio” as used herein means the weight of filament-formingmaterial (g or %) on a dry weight basis in the filament to the weight ofadditive, such as active agent(s) (g or %) on a dry weight basis in thefilament.

“Hydroxyl polymer” as used herein includes any hydroxyl-containingpolymer that can be incorporated into a filament of the presentinvention, for example as a filament-forming material. The hydroxylpolymer of the present invention comprises greater than 10% and/orgreater than 20% and/or greater than 25% by weight hydroxyl moieties.

“Water-soluble material” as used herein means a material that ismiscible in water. In other words, a material that is capable of forminga stable (i.e. does not separate for greater than 5 minutes afterforming the homogeneous solution) homogeneous solution or dispersionwith water at ambient conditions.

“Water soluble filament” as used herein refers to the water solubilityof the filament after completion of the filament forming process anddoes not include unless specifically stated filaments which havesubsequent treatments such as subsequently coating with an additive.

“Ambient conditions” as used herein means 73° F.±4° F. (about 23°C.±2.2° C.) and a relative humidity of 50%±10%.

“Length” as used herein, with respect to a filament, means the lengthalong the longest axis of the filament from one terminus to the otherterminus. If a filament has a kink, curl or curves in it, then thelength is the length along the entire path of the filament.

“Diameter” as used herein, with respect to a nano-filament or filament,is measured according to the Diameter Test Method described herein. Inone example, a filament of the present invention exhibits a diameter ofless than 100 μm and/or less than 75 μm and/or less than 50 μm and/orless than 25 μm and/or less than 20 μm and/or less than 15 μm and/orless than 10 μm and/or less than 6 μm and/or greater than 1 μm and/orgreater than 3 μm.

“By weight on a dry filament basis” means that the weight of thefilament measured immediately after the filament has been conditioned ina conditioned room at a temperature of 73° F.±4° F. (about 23° C.±2.2°C.) and a relative humidity of 50%±10% for 2 hours. In one example, “byweight on a dry filament basis” means that the filament comprises lessthan 20% and/or less than 15% and/or less than 10% and/or less than 7%and/or less than 5% and/or less than 3% and/or to 0% and/or to greaterthan 0% based on the weight of the filament of moisture, such as water,for example free water, as measured according to the Water Content TestMethod described herein.

“Total level” as used herein, for example with respect to the totallevel of one or more active agents present in the filament, means thesum of the weights or weight percent of all of the subject materials,for example active agents. In other words, a filament may comprise 25%by weight on a dry filament basis of an anionic surfactant, 15% byweight on a dry filament basis of a nonionic surfactant, 10% by weightof a chelant, and 5% of a perfume so that the total level of activeagents present in the filament is greater than 50%; namely 55% by weighton a dry filament basis.

“Web” as used herein means a collection of formed filaments, such as afibrous structure, and/or a sheet formed of filaments, such ascontinuous filaments, of any nature or origin associated with oneanother. In one example, the web is a sheet that is formed via aspinning process, not a cast process.

“Nonwoven web” for purposes of the present invention as used herein andas defined generally by European Disposables and Nonwovens Association(EDANA) means a sheet of filaments, such as continuous filaments, of anynature or origin, that have been formed into a web by any means, and maybe bonded together by any means, with the exception of weaving orknitting. Felts obtained by wet milling are not nonwoven webs.

“Particulates” as used herein means granular substances and/or powders.

“Coating” as used herein means the addition of an additive, such as askin care active agent for example onto at least a portion of thesurface of the filaments and/or the web or the voids within the web. Thecoating may be applied to the individual filaments and/or may be appliedonto the web and the voids therein. The coating may be uniform orapplied on or into discrete areas of the filament or web. Coating may beapplied by any means known in the art such as, but not limited to, spraycoating, dip coating, slot coating, printing such as gravure, flexo andinkjet or combinations thereof. The coating may be retained on thesurface of the filament of the web to which it is applied or may atleast partially impregnate the filaments or web or fill voids within theweb.

“Laminate” as used herein is defined as comprising at least two layersof superimposed web, which are bonded together. The layers may be bondedtogether using for example temperature, pressure and/or the applicationof water or a thermosetting material, or ultrasound or combinationsthereof.

As used herein, the articles “a” and “an” when used herein, for example,“an anionic surfactant” or “a filament” is understood to mean one ormore of the material that is claimed or described. All percentages andratios are calculated by weight unless otherwise indicated. Allpercentages and ratios are calculated based on the total compositionunless otherwise indicated. Unless otherwise noted, all component orcomposition levels are in reference to the active level of thatcomponent or composition, and are exclusive of impurities, for example,residual solvents or by-products, which may be present in commerciallyavailable sources.

Filament

The shaving aid or razor cartridge housing of the present inventioncomprises filaments wherein at least 15%, or at least 30%, or at least40% or at least 50% or at least 60% or at least 70% or at least 80% orat least 90% by weight of total filament are water soluble filaments.The water-soluble filaments of the present invention preferably compriseone or more filament-forming materials which may comprise one or morefilament-forming lubricating materials. The filament forming materialsare preferably water soluble. The shaving aid or razor cartridge housingmay optionally further independently comprise 85% or less, 70% or less,or 60% or less, or 50% or less or 40% or less, or 30% or less, or 20% orless or 10% or less or 5% or less by weight of the total filaments ofone or more non-water soluble filaments and or non-water solublefilament forming materials and or water. The water-soluble filaments mayoptionally also further comprise water and or one or more additives andmay include one or more skin care active agents.

The filament of the present invention preferably comprises 0% to lessthan 20%, even more preferably 0% to less than 15%, even more preferablystill 2% to less than 10% by weight of water as measured according tothe Water Content Test Method described herein.

In one embodiment, the filament may comprise one or more water solublefilament-forming lubricating materials. In another embodiment thefilament may comprise one or more additives. In another embodiment thefilament may comprise one or more skin care active agents selected fromthe group consisting of: surfactants, fats, oils, waxes, quaternaryammonium polymers, humectants, occlusive agent, cationic polymers,sensates, chronic skin care actives, perfume and anti-perspirantactives. In another embodiment, the water-soluble filament comprises atotal level of additives of from about 0% to about 70% and a total levelof skin care active agents of from about 0% to about 70%. In anotherembodiment the skin care active agents may be present from about 1% toabout 15% by weight of the water-soluble filament and or filaments.

The filament may comprise two or more different skin care active agents.The two or more different skin care active agents, may be compatible orincompatible with one another. The filament may comprise an active agentwithin the filament and an active agent on at least a portion of anexternal surface of the filament, such as a coating on the filament. Theactive agent on the external surface of the filament may be the same ordifferent from the active agent present in the filament. If different,the active agents may be compatible or incompatible with one another.Filaments comprising different skin care active agents are alsoenvisaged.

The one or more skin care active agents may be uniformly distributed orsubstantially uniformly distributed throughout the filament or may bedistributed as discrete regions within the filament. The skin activeagents described hereinafter may also be used as a coating as describedhereinafter.

The filaments of the present invention may be meltblown, spun bond orelectrospun filaments. In the case of meltblown or spunbond filamentspreferably the filament exhibits a diameter of less than 100 μm, morepreferably less than 50 μm, even more preferably less than 25 μm, evenmore preferably still and/or less than 10 as measured according to theDiameter Test Method described herein. In the case of electrospunfilaments, the filament of the present invention preferably exhibits adiameter of less than 1 μm as measured according to the Diameter TestMethod described herein. The diameter of a filament of the presentinvention may be used to control the dissolution rate of the filamentand delivery of the water-soluble lubricating materials and/or skin careactive agents under the conditions of use.

The filaments are intended for use on a hair removal head, such as arazor cartridge, and may be incorporated as is, attached onto anotherelement of the hair removal head such as the housing of a razorcartridge or shaving aid and/or be used to form a discrete article suchas a shaving aid for use on the hair removal head or cartridge.

Filament-Forming Material

The filament-forming material is any suitable material, such as apolymer or monomers capable of producing a polymer that exhibitsproperties suitable for making a filament, such as by a spinningprocess. The filament forming material preferably comprises at least15%, preferably at least 30%, more preferably at least 50% by weight ofa water-soluble filament forming material. The filament forming materialmay comprise up to about 70% by weight, preferably less than 50%, morepreferably less than 25%, even more preferably less than 10% by weightof a non-water soluble filament forming material and or additive.

In one embodiment the filament forming material comprises at least onelubricating filament-forming material(s) preferably water solublelubricating filament forming materials selected from the groupconsisting of: polymers derived from acrylic monomers such as theethylenically unsaturated carboxylic monomers and ethylenicallyunsaturated monomers, polyvinyl alcohol, polyacrylates,polymethacrylates, copolymers of acrylic acid and methyl acrylate,polyvinylpyrrolidones, polyethylene oxide, polyethylene glycol,polpolyacrylamides, starch and starch derivatives, natural or syntheticgums pullulan, gelatin, hydroxypropylmethylcelluloses, methycelluloses,quaternary ammonium polymers and carboxymethycelluloses. Preferably thematerials may be selected from a nonionic polymer for examplepolyethyleneglycol and or polyethyleneoxide, a hydroxyl polymer, such asa polyvinyl alcohol (“PVOH” or “PVA”) and/or a quaternary ammoniumpolymer, or combinations thereof.

a. Water-Soluble Hydroxyl Polymers

Non-limiting examples of water-soluble hydroxyl polymers in accordancewith the present invention include polyols, such as polyvinyl alcohol,polyvinyl alcohol derivatives, polyvinyl alcohol copolymers, starch,starch derivatives, starch copolymers, chitosan, chitosan derivatives,chitosan copolymers, cellulose derivatives such as cellulose ether andester derivatives, cellulose copolymers, hemicellulose, hemicellulosederivatives, hemicellulose copolymers, gums, arabinans, galactans,proteins and various other polysaccharides and mixtures thereof.

Polyvinyl alcohols herein can be grafted with other monomers to modifyits properties. A wide range of monomers has been successfully graftedto polyvinyl alcohol. Non-limiting examples of such monomers includevinyl acetate, styrene, acrylamide, acrylic acid, 2-hydroxyethylmethacrylate, acrylonitrile, 1,3-butadiene, methyl methacrylate,methacrylic acid, maleic acid, itaconic acid, sodium vinylsulfonate,sodium allylsulfonate, sodium methylallyl sulfonate, sodiumphenylallylether sulfonate, sodium phenylmethallylether sulfonate,2-acrylamido-methyl propane sulfonic acid (AMPs), vinylidene chloride,vinyl chloride, vinyl amine and a variety of acrylate esters.

In one example, the water-soluble hydroxyl polymer is selected from thegroup consisting of: polyvinyl alcohols, hydroxymethylcelluloses,hydroxyethylcelluloses, hydroxypropylmethylcelluloses and mixturesthereof. A non-limiting example of a suitable polyvinyl alcohol includesthose commercially available from Kuraray (Japan) under the POVAL®tradename, preferably KL318 and/or 420H grades.

b. Non-Ionic Polymer

Examples of suitable non-ionic water soluble polymers suitable for usehererin include polyethylene oxide, polyvinyl pyrrolidone,polyacrylamide, polyvinyl imidazoline, polyethylene glycol, and mixturesthereof. In some embodiments, said water soluble polymer is selectedfrom the group consisting of polyethylene oxide and polyethylene glycol,and mixtures thereof.

One group of preferred water soluble polymers are the polyethyleneoxides generally known as POLYOX′ (available from Dow Chemicals) orALKOX′ (available from Meisei Chemical Works, Kyoto, Japan). Thepolyethylene oxides, may have average molecular weights of at leastabout 20,000, preferably at least about 50,000, preferably at leastabout 100,000 or from about 100,000 to about 8 million, more preferablyabout 300,000 to about 5 million.

Another group of preferred water soluble polymers are polyethyleneglycols generally known as PEGs and available as CARBOWAX® (from DowChemicals) and PLURIOL′ (from BASF). The polyethylene glycols may havean average molecular weight of from about 200 to about 8,000, preferablyfrom about 200 to about 600, even more preferably from about 350 toabout 450.

In some embodiments it may be advantageous to combine polyethyleneoxides with polyethylene glycols.

c. Quaternary Ammonium Polymers

Suitable water soluble cationic polymers are, for example, cationiccellulose derivatives, for example a quaternized hydroxymethyl celluloseobtainable under the name UCARE POLYMER JR 400® from Dow, hydrophobizedquaternized hydroxymethyl cellulose, for example SOFTCAT® SL-5 from Dow,cationic starches, copolymers of diallylammonium salts and acrylamides,copolymers of diallylammonium salts and acrylic acid (MERQUAT® 280 fromLubrizol), quaternized vinylpyrrolidone/vinyl imidazole polymers, forexample LUVIQUAT® (BASF), condensation products of polyglycols andamines, quaternized collagen polypeptides, for example lauryldimoniumhydroxypropyl hydrolyzed collagen (LAMEQUAT® L/Grünau), quaternisedwheat polypeptides, polyethyleneimine, cationic silicone polymers, forexample amidomethicones, copolymers of adipic acid andDimethyl-aminohydroxypropyldiethylene-triamine (CARTARETIN®/Clariant),copolymers of acrylic acid with dimethyldiallylammonium chloride(MERQUAT® 550/Chemviron), polyaminopolyamides, as described, forexample, in FR-A-2 252840, and the cross-linked water-soluble polymersthereof, cationic chitin derivatives, for example of quaternisedchitosan, optionally distributed as microcrystals; condensation productsof dihaloalkyls, for example dibromobutane, with bisdialkylamines, forexample bisdimethylamino-1,3-propane, cationic guar gum, for exampleJAGUAR® C-17 from Celanese or N-HANCE® 3196 from Ashland, quaternisedammonium salt polymers, for example MIRAPOL® A-15, MIRAPOL® AD-1,MIRAPOL® AZ-1 from Miranol, ampholytic terpolymers comprised ofmethacrylamidopropyl trimethyl ammonium chloride, acrylamide and acrylicacid, for example MERQUAT® 2003PR.

In one embodiment the filament forming material is selected frompolyvinyl alcohol, polyethylene oxide, polyethylene glycol and mixturesthereof. In other embodiment, the filament forming material is selectedfrom polyethylene oxide. In other example the filament forming materialis selected from a quaternary ammonium polymer, preferably a copolymerof a diallylammonium salt and acrylic acid.

Nano-Filaments

As explained above, nano-filaments can be made up of the same polymers,monomers, or mixtures thereof as described above with regards tofilaments. In one embodiment, the invention comprises a shaving aidcomprising at least one nano-filament. In one embodiment, the inventioncomprises a shaving aid comprising a second nano-filament. In oneembodiment, the invention comprises a shaving aid comprising a mixtureof two or more different nano-filaments. In one embodiment, theinvention comprises a shaving aid comprising a filament and anano-filament.

In one embodiment, the nano-filament consists essentially of one or morewater soluble polymers. Suitable polymers for forming the nano-filamentinclude polyvinylalcohol, quaternary ammonium polymer, polyethyleneglycol, polyethyleneoxide, polypropylene oxide, or a combinationthereof. In one embodiment, the nano-filament is a copolymer ofpolyethylene oxide and polypropylene oxide, such as those disclosed inU.S. Pat. No. 5,454,164, EP2988831A and EP2988832A.

In one embodiment, the nano-filaments are cross linked. One way to crosslink the nano-filaments is to use a modified water soluble polymer suchas a modified PEO. In one embodiment, the PEO has been modified toprevent its dissolution in water. Without intending to be bound bytheory, it is believed that when nanofibers based on water-solublepolymers are crosslinked, they only swell in an aqueous solution andform hydrogels. This has been explained in Zhou et al, UV-initiatedcrosslinking of electrospun poly(ethylene oxide) nanofibers withpentaerythritol triacrylate: Effect of irradiation time and incorporatedcellulose nanocrystals. Carbohydrate Polymers 87 (2012) 1779-1786.Specific crosslinking mechanisms can include treatment by UVirradiation. In such a situation the PETA could form an excited tripletstate, and then absorb a proton from PEO chain and cleave C══O bond ofPETA to form a PEO radical and a PETA radical, respectively. PEO radicalproduced attacks the C══C bond of PETA to initiate the polymerization ofPETA. These obtained chains are terminated through radical coupling toform the crosslinking between PEO and PETA

In another embodiment, the nano-filament also comprise non-water solublecomponents. In one embodiment, the nano-filament has a water-solublesheath surrounding a non-soluble core, referred to herein as a co-axialnano-filament. In one embodiment, the co-axial nano-filament comprisesat least two components, wherein said two components are immiscible. Thecore can be in liquid or solid form. The core can comprise a non-solublematerial. The core can also comprise a hydrophobic material. Preferably,the core comprises a skin care active. One type of co-axialnano-filament for use with the present invention comprises PEO sheathformed around a liquid polydimethylsiloxane silicone core (PMX-200 byDow Corning at 200 cSt viscosity). In one embodiment the core has adiameter of from about 90 nm to about 900 nm. In one embodiment, thesheath has a diameter of from about 100 nm to 1000 nm. In oneembodiment, the co-axial nano-filament has more than one sheathsurrounding the core. One embodiment of the present invention providesfor a method of making a shaving aid comprising a co-axialnano-filament. One way to make such a filament is to use a specialtycoaxial emitter tip and an extra syringe pump to drive two fluidsconcentrically inside one another into the charged field used toelectrospin the nano-filament. The electrospinning process forms fibersfrom those two starting fluids while maintaining their concentricgeometry.

In one embodiment the nano-filament has a diameter of from about 10 nmto about 1000 nm, preferably from about 250 nm to about 750 nm, about300 nm to about 600 nm, or even about 350 to about 550 nm. Those ofordinary skill in the art will understand that the average diameter canbe calculated using an imaging analysis technique. One suitable imaginganalysis technique is to use a field emission scanning electronmicroscopy (FESEM). One way to do this is to sputter coat the fibersubstrate or web with an electrically conductive metal (such as gold,platinum, silver, chromium, or iridium) and then examine the filamentsusing FESEM. Specifically, in one embodiment, gold is sputter coatedonto the fiber sample for 30 seconds prior to FESEM imaging. Imaging isthen performed with a Hitachi S-4200 FESEM and filament diametermeasurements are collected using ImageJ to analyze the SEM images. Inone embodiment at least one filament in the shaving aid is anano-filament. In another embodiment where a plurality of filaments arepresent having a diameter less than 1000 nm, the average diameter ofsuch nano-filaments can be from about 300 nm to about 600 nm, preferablyfrom about 350 nm to about 550 nm.

Skin Care Active Agents

In one embodiment the filament, web or shaving aid may comprise a “Skincare active agent”. Non-limiting examples of suitable cosmetic agents,skin care agents and, skin conditioning agents, are described in CTFACosmetic Ingredient Handbook, Second Edition, The Cosmetic, Toiletries,and Fragrance Association, Inc. 1988, 1992 and include fats, oils,waxes, surfactants, perfumes, humectants, quaternary polymers, coolingagents and mixtures thereof. In one embodiment, the skin care activeagents are hydrophobic. The skin care active agents may be utilized toprovide both immediate and single application benefits and or to addresschronic skin conditions requiring multiple applications. The skin careactive agents may be present within the filament, on a portion of theexternal surface thereof or may be applied as a coating on the formedweb as discussed hereinafter.

i. Fats, Oils and Waxes

Suitable oils may be selected from natural oil, synthetic oil, siliconeoil and mixtures thereof. Non-limiting examples of suitable natural oilsinclude Acetylated Castor Oil, Acetylated Hydrogenated Castor Oil,Actinidia Chinensis (Kiwi), Seed Oil, Adansonia Digitata Oil, AleuritesMoluccana Seed Oil, Anacardium Occidentale (Cashew) Seed Oil, ArachisHypogaea (Peanut) Oil, Arctium Lappa Seed Oil, Argania Spinosa KernelOil, Argemone Mexicana Oil, Avena Sativa (Oat) Kernel Oil, BertholletiaExcelsa Seed Oil, Borago Officinalis Seed Oil, Brassica Campestris(Rapeseed) Seed Oil, Calophyllum Tacamahaca Seed Oil, Camellia JaponicaSeed Oil, Camellia Kissi Seed Oil, Camellia Oleifera Seed Oil, CanolaOil, Caprylic/Capric/Lauric Triglyceride, Caprylic/Capric/LinoleicTriglyceride, Caprylic/Capric/My-ristic/Stearic Triglyceride,Caprylic/Capric/Stearic Triglyceride, Caprylic/Capric Triglyceride,Carthamus Tinctorius (Hybrid Safflower) Seed Oil, Carthamus Tinctorius(Safflower) Seed Oil, Carum Carvi (Caraway) Seed Oil, Carya Illinoensis(Pecan) Seed Oil, Castor Oil Benzoate, Chenopodium Quinoa Seed Oil,Cibotium Barometz Oil, Citrullus Vulgaris (Watermelon) Seed Oil, CocosNucifera (Coconut) Oil, Coffea Arabica (Coffee) Seed Oil, CoixLacryma-Jobi (Job's Tears) Seed Oil, Corylus Americana (Hazel) Seed Oil,Corylus Avellana (Hazel) Seed Oil, Cucumis Sativus (Cucumber) Oil,Cucurbita Pepo (Pumpkin) Seed Oil, Daucus Carota Sativa (Carrot) SeedOil, Elaeis Guineensis (Palm) Kernel Oil, Elaeis Guineensis (Palm) Oil,Gossypium (Cotton) Seed Oil, Helianthus Annuus (Hybrid Sunflower) Oil,Helianthus Annuus (Sunflower) Seed Oil, Hippophae Rhamnoides Oil, HumanPlacental Lipids, Hydrogenated Canola Oil, Hydrogenated Castor Oil,Hydrogenated Castor Oil Laurate, Hydrogenated Castor Oil Triisostearate,Hydrogenated Coconut Oil, Hydrogenated Cottonseed Oil, HydrogenatedC12-18 Triglycerides, Hydrogenated Fish Oil, Hydrogenated Lard,Hydrogenated Menhaden Oil, Hydrogenated Olive Oil, Hydrogenated OrangeRoughy Oil, Hydrogenated Palm Kernel Oil, Hydrogenated Palm Oil,Hydrogenated Peanut Oil, Hydrogenated Rapeseed Oil, Hydrogenated SharkLiver Oil, Hydrogenated Soybean Oil, Hydrogenated Sunflower Seed Oil,Hydrogenated Tallow, Hydrogenated Vegetable Oil, lsatis Tinctoria SeedOil, Juglans Regia (Walnut) Seed Oil, Lauric/Palmitic/OleicTriglyceride, Umnanthes Alba (Meadowfoam) Seed Oil, Unum sitatissimum(Linseed) Seed Oil, Lupinus Albus Seed Oil, Macadamia Integrifolia SeedOil, Macadamia Ternifolia Seed Oil, Maleated Soybean Oil, MangiferaIndica (Mango) Seed Oil, Marmot Oil, Melaleuca Alternifolia (Tea Tree)Leaf Oil, Melia Azadirachta Seed Oil, Melissa Officina lis (Balm Mint)Seed Oil, Menhaden Oil, Moringa pterygosperma Seed Oil, Mortierella Oil,Neatsfoot Oil, Nelumbium Speciosum Flower Oil, Nigella Sativa Seed Oil,Oenothera Biennis (Evening Primrose) Oil, Olea Europaea (Olive) FruitOil, Olea Europaea (Olive) Husk Oil, Orange Roughy Oil, Orbignya CohuneSeed Oil, Orbignya Oleifera Seed Oil, Oryza Sativa (Rice) Bran Oil,Oryza Sativa (Rice) Germ Oil, Ostrich Oil, Oxidized Corn Oil, OxidizedHazel Seed Oil, Papaver Orientale (Poppy) Seed Oil, Passiflora EdulisSeed Oil, Persea Gratissima (Avocado) Oil, Pistacia Vera Seed Oil,Placental Lipids, Prunus Amygdalus Amara (Bitter Almond) Kernel Oil,Prunus Amygdalus Dulcis (Sweet Almond) Oil, Prunus Armeniaca (Apricot)Kernel Oil, Prunus Avium (Sweet Cherry) Seed Oil, Prunus Cerasus (BitterCherry) Seed Oil, Prunus Persica (Peach) Kernel Oil, Pyrus Malus (Apple)Oil, Ribes Nigrum (Black Currant) Seed Oil, Ricinus Communis (Castor)Seed Oil, Rosa Canina Fruit Oil, Rosa Moschata Seed Oil, SalviaHispanica Seed Oil, Santalum Album (Sandalwood) Seed Oil, SesamumIndicum (Sesame) Seed Oil, Solanum Lycopersicum (Tomato) Seed Oil,Soybean Lipid, Sphingolipids, Taraktogenos Kurzii Seed Oil, TelphairiaPedata Oil, Vegetable Oil, Vitis Vinifera (Grape) Seed Oil, Zea Mays(Corn) Germ Oil, Zea Mays (Corn) Oil mineral oil and mixtures thereof.

Suitable synthetic oils include hydrocarbons, esters, alkanes, alkenesand mixtures thereof. Non-limiting examples include isopropyl palmitate,isopropyl stearate, isohexadecane, isododecane, polyglyceryltriisostearate and mixtures thereof.

Non-limiting examples of suitable silicone oils include dimethicones(including partial esters of dimethicones and fatty acids derived fromnatural/synthetic oils), cyclomethicones, phenylated silicones, phenyltrimethicones, trimethyl pentaphenyl trisiloxane and mixtures thereof.

Non-limiting examples of commercially available silicone oils includeDow Corning 200 fluid, Dow Corning 244, Dow Corning 245, Dow Corning344, and Dow Corning 345, (commercially available from Dow CorningCorp.); SF-1204 and SF-1202 Silicone Fluids (commercially available fromG.E. Silicones), GE 7207 and 7158 (commercially available from GeneralElectric Co.); and SWS-03314 (commercially available from SWS SiliconesCorp.), the Viscasil series (sold by General Electric Company), SF 1075methyl-phenyl fluid (sold by General Electric Company) and 556 CosmeticGrade Fluid (sold by Dow Corning Corp.), Silshine 151 (sold byMomentive), PH1555 and PH1560 (sold by Dow Corning) and Silwets such asSilwets 7210, 7230 and 7220 (available from by Momentive).

Suitable triglycerides, may have the following formula:

wherein R, R′ and R″ may be the same as or different from one or both ofthe others, wherein each of R, R′ and R″ is a fatty acid and wherein theor each triglyceride is solid at 25° C.

Suitable oils from which triglycerides may be formed from include, butare not limited to, the oils listed herein. Suitable fatty acids forformation of triglycerides include, but are not limited to, Myristoleicacid, Palmitoleic acid, Sapienic acid, Oleic acid, Linoleic acid,α-Linolenic acid, Arachidonic acid, Eicosapentaenoic acid,Docosahexaenoic acid, Lauric acid (C₁₂), Myristic acid (C₁₄), Palmiticacid (C₁₆), Stearic acid (C₁₈), Arachidic acid (C₂₀) and mixturesthereof.

Specific sources of triglycerides suitable for inclusion herein includeShea Butter, Theobroma acao (Cocoa) Seed Butter, Cocoa Butter, MangiferaIndica (Mango) Seed Butter, Kokum Butter and mixtures thereof.Particularly preferred are shea butter, cocoa butter and mixturesthereof.

The wax may comprise natural wax, synthetic wax or mixtures thereof.Natural waxes may be plant, animal or mineral derived. Non-limitingexamples of suitable natural waxes include Beeswax, Copernicia Cerifera(Carnauba) Wax, Euphorbia Cerifera (Candelilla) Wax, Jojoba Wax, OryzaSativa (Rice) Bran Wax, Lemon peel wax, Soybean wax, Sunflower wax andmixtures thereof.

Non-limiting examples of suitable synthetic waxes include HydrogenatedJojoba Wax, synthetic and siliconyl jojoba wax, HydrogenatedMicrocrystalline Wax, Microcrystalline Wax, synthetic, siliconyl andHydrogenated Rice Bran Wax, Ceresin, Ozokerite, Paraffin, benhenylbeeswax, synthetic, siliconyl and hydrogenated Beeswax, synthetic,hydrogenated and siliconyl Candelilla Wax, Synthetic, hydrogenated andsiliconyl Carnauba wax, synthetic, hydrogenated and siliconyl lemon peelwax, synthetic, siliconyl and hydrogenated soybean wax, synthetic,siliconyl and hydrogenated sunflower wax and mixtures thereof. Preferrednatural and synthetic waxes are Beeswax, Microcrystalline wax,Candellila wax, Ozokerite, and mixtures thereof.

Non-limiting examples of suitable silicone waxes include, Stearyoxytrimethylsilane such as DC580 wax, C30-45 alkyl methicone available asDC AMS-C30 Cosmetic Wax, stearyoxymethyl silane available as DC Silkywax10, C24-54 alkyl methicone such as DC ST-Wax 30, C30-45Alkyldimethylsilyl, Polypropyl-silsesquioxane, available as DC SW-8005resin wax, and mixtures thereof.

Particularly preferred oils, waxes or fats suitable as skin care activeagents are selected from PDMS silicone fluids, mineral oil, andpetrolatum, naturally derived oils such as olive oil derivatives ormixtures thereof. In one example, fats, oils and/or waxes are present inranges from about 0.01% to about 60% w/w on a dry weight basis of thewater-soluble filament, preferably from about 1% to about 40%, morepreferably from about 5% to about 30% by weight of the water-solublefilament.

In another example, the amount of fats, oils and/or waxes may be presentas a coating on the filaments or formed web. In such embodiments, thefats, oils and/or waxes may be e present in weight ratios of about 4:1(web:fats, oils and/or waxes) to about 1:8 (web:fats, oils and/orwaxes). In such embodiments the fats, oils and/or waxes may be presentin or on the surface of the individual filaments and or applied as acoating to formed web as discussed hereinafter.

ii. Surfactants

Non-limiting examples of suitable surfactants include anionicsurfactants, cationic surfactants, nonionic surfactants, zwitterionicsurfactants, amphoteric surfactants, and mixtures thereof.

a. Anionic Surfactants

Non-limiting examples of suitable anionic surfactants include alkylsulfates, alkyl ether sulfates, branched alkyl sulfates, branched alkylalkoxylates, branched alkyl alkoxylate sulfates, mid-chain branchedalkyl aryl sulfonates, sulfated monoglycerides, sulfonated olefins,alkyl aryl sulfonates, primary or secondary alkane sulfonates, alkylsulfosuccinates, acyl taurates, acyl isethionates, alkyl glycerylethersulfonate, sulfonated methyl esters, sulfonated fatty acids, alkylphosphates, acyl glutamates, acyl sarcosinates, alkyl sulfoacetates,acylated peptides, alkyl ether carboxylates, acyl lactylates, anionicfluorosurfactants, sodium lauroyl glutamate, and combinations thereof.

Alkyl sulfates and alkyl ether sulfates suitable for use herein includematerials with the respective formula ROSO₃M and RO(C₂H₄O)_(x)SO₃M,wherein R is alkyl or alkenyl of from about 8 to about 24 carbon atoms,x is 1 to 10, and M is a water-soluble cation such as ammonium, sodium,potassium and triethanolamine Other suitable anionic surfactants aredescribed in McCutcheon's Detergents and Emulsifiers, North AmericanEdition (1986), Allured Publishing Corp. and McCutcheon's, FunctionalMaterials, North American Edition (1992), Allured Publishing Corp.

b Nonionic Surfactants

Non-limiting examples of non-ionic surfactants are co-polymers ofpolyethylene oxide (PEO) and polypropylene oxide (PPO) and copolymers ofpolysorbate and a fatty acid. Commercially these materials are availableunder the tradenames of PLURONICS® and TWEENs® respectively.

The PEO/PPO copolymer may have any average molecular weight.Advantageously, the PEO/PPO copolymer has an average molecular weight ofat least 5,000, preferably in the range f from 10,000 to 20,000, morepreferably from 11,000 to 15,000, even more preferably from 12,000 to13,000 and even more preferably still from 12,250 to 12,750. Withoutwishing to be bound by theory, the inclusion of a PEO/PPO copolymer ofsufficient molecular weight is thought to further improve thelubrication properties of the water-soluble polymer in aqueous solution,especially for polyethylene oxide, and thus prevent an undesirablefeeling in use.

The PEO/PPO copolymer may be of any arrangement but is advantageously ablock copolymer, for example a di-block, tri-block, multi-block,radial-block or random-block copolymer. Preferably, the PEO/PPOcopolymer is a tri-block copolymer, more preferably a tri-blockcopolymer having the sequence: PEO-PPO-PEO. Such tri-block copolymers ofPEO and PPO are commercially available under tradenames such asPLURACARE® from BASF and PLURONIC® from Sigma-Aldrich.

TWEENs™ are ethoxylated esters formed by esterification of sorbitol witha fatty acid. Both the degree of ethoxylation and esterification can bemodified as can the length of the fatty acid alkyl chain. For examplethe fatty acid chain can range from lauric acid (C12) to stearic (C18)and oleic (C18:1) acid. Ethoxylation can vary from 4 to 20 units.Increasing the degree of ethoxylation and decreasing the molecularweight of the fatty acid chain both increase the aqueous solubility ofthe material and so increase the HLB. Preferably TWEENS are selected inwhich hydrophilic behavior dominates, these are typically TWEENs with anHLB of 11 or above. Preferably the HLB is at least 11, even morepreferably it is above 13 and most preferred are an HLB of above 15.

The concentration of non-ionic surfactants typically ranges from about0.01% to about 15% w/w on a dry weight basis of the filament or of theweb.

c. Zwitterionic Surfactants

Non-limiting examples of zwitterionic or ampholytic surfactants include:derivatives of secondary and tertiary amines, derivatives ofheterocyclic secondary and tertiary amines, or derivatives of quaternaryammonium, quaternary phosphonium or tertiary sulfonium compounds. SeeU.S. Pat. No. 3,929,678 at column 19, line 38 through column 22, line48, for examples of zwitterionic surfactants; betaines, including alkyldimethyl betaine and cocodimethyl amidopropyl betaine, C₈ to C₁₅ (forexample from C₁₂ to C₁₅) amine oxides and sulfo and hydroxy betaines,such as N-alkyl-N, N-dimethylammino-1-propane sulfonate where the alkylgroup can be C₈ to C₁₅ and in certain embodiments from C₁₀ to C₁₄.

iii. Perfumes

One or more perfume and/or perfume raw materials such as accords and/ornotes or perfumery ingredients may be incorporated into one or more ofthe filaments or web or shaving aid of the present invention. Theperfume may comprise a perfume ingredient selected from the groupconsisting of: aldehyde perfume ingredients, ketone perfume ingredients,and mixtures thereof.

A wide variety of natural and synthetic chemical ingredients useful asperfumes and/or perfumery ingredients include but not limited toaldehydes, ketones, esters, and mixtures thereof. Also included arevarious natural extracts and essences which can comprise complexmixtures of ingredients, such as orange oil, lemon oil, rose extract,lavender, musk, patchouli, balsamic essence, sandalwood oil, pine oil,cedar, and the like. Finished perfumes can comprise extremely complexmixtures of such ingredients. Typically, a finished perfume comprisesfrom about 0.01% to about 2%, by weight on a dry filament basis dry webbasis or as a % w/w of the shaving aid.

The perfume may be included as the raw material or included in a perfumedelivery system, including but not limited to a cyclodextrin, afrangible micro-sphere, an inorganic carrier material or a starchencapsulated accord or mixture thereof.

iv. Quaternary Ammonium Polymers

The filaments, webs and shaving aids of the present invention mayadditionally further comprise a cationic polymer as a skin conditioningagent. Such polymers may also be utilized as filament forming materialsbut may further be added to the formed filaments or web as a coating todeliver further skin conditioning benefits. Concentrations of thecationic polymer in the filaments when present as a coating, typicallyrange from about 0.05% to about 3% and/or from about 0.075% to about2.0% and/or from about 0.1% to about 1.0% by weight on a dry filamentbasis. Alternatively, the coating composition may comprise a quaternaryammonium polymer and is preferably present from 0% to 20% w/w, morepreferably from 0% to 10% w/w, of the filament, web and or shaving aid.

Non-limiting examples of suitable cationic polymers may have cationiccharge densities of at least 0.5 meq/gm and/or at least 0.9 meq/gmand/or at least 1.2 meq/gm and/or at least 1.5 meq/g at a pH of fromabout 3 to about 9 and/or from about 4 to about 8. In one example,cationic polymers suitable as conditioning agents may have cationiccharge densities of less than 7 meq/gm and/or less than 5 meq/gm at a pHof from about 3 to about 9 and/or from about 4 to about 8. Herein,“cationic charge density” of a polymer refers to the ratio of the numberof positive charges on the polymer to the molecular weight of thepolymer. The weight average molecular weight of such suitable cationicpolymers will generally be between about 10,000 and 10 million, in oneembodiment between about 50,000 and about 5 million, and in anotherembodiment between about 100,000 and about 3 million.

Suitable cationic polymers for use herein may contain cationicnitrogen-containing moieties such as quaternary ammonium and/or cationicprotonated amino moieties. Any anionic counterions may be used inassociation with the cationic polymers so long as the cationic polymersremain soluble in water and so long as the counterions are physicallyand chemically compatible with the other components of the filaments ordo not otherwise unduly impair product performance, stability oraesthetics of the filaments. Non-limiting examples of such counterionsinclude halides (e.g., chloride, fluoride, bromide, iodide), sulfatesand methylsulfates. Non-limiting examples of such cationic polymers aredescribed in the CTFA Cosmetic Ingredient Dictionary, 3rd edition,edited by Estrin, Crosley, and Haynes, (The Cosmetic, Toiletry, andFragrance Association, Inc., Washington, D.C. (1982)).

Other suitable cationic polymers for use in the filaments, webs orshaving aid of the present invention include cationic polysaccharidepolymers, cationic guar gum derivatives, quaternary nitrogen-containingcellulose ethers, cationic synthetic polymers, cationic copolymers ofetherified cellulose, guar and starch. When used, the cationic polymersherein are soluble in water. Further, suitable cationic polymers for usein the filaments of the present invention are described in U.S. Pat. No.3,962,418, U.S. Pat. No. 3,958,581, and U.S. 2007/0207109A1, which areall incorporated herein by reference.

The concentration of the conditioning agents in the filaments, webs andor shaving aid may be sufficient to provide the desired conditioningbenefits. Such concentration can vary with the conditioning agent, theconditioning performance desired, the average size of the conditioningagent particles, the type and concentration of other components, andother like factors and may be selected accordingly.

v. Humectants

The filaments, webs or having aids of the present invention may containone or more humectants. The humectants herein are selected from thegroup consisting of polyhydric alcohols, water soluble alkoxylatednonionic polymers, and mixtures thereof.

vi. Coolant Compounds

The filaments, webs or shaving aids of the present invention may containone or more coolant compounds. A large number of coolant compounds ofnatural or synthetic origin are known. Among natural coolants,peppermint oil, camphor, eucalyptus oil, thymol and lavender oil are themost common. Among synthetic coolants, many are derivatives of or arestructurally related to menthol, i.e., containing the cyclohexanemoiety, and derivatized with functional groups including carboxamide,ketal, ester, ether and alcohol. Non-limiting examples include methylmethylamido oxalate, (under the tradename FRESCOLAT X-COOL® availablefrom Symrise), menthyl lactate (such as FRESCOLAT MLJ Natural availablefrom Symrise), and Menthyl Pyrrolidone Carboxylate also known as MenthylPCA (under the tradename QUESTICES® available from Givaudan).

vii. Color Agents

The filaments, webs or shaving aids of the present invention maycomprise one or more color agents or colorants. The color agents may beused in amounts effective to produce a desired color. The color agentsuseful in the present invention include pigments such as titaniumdioxide and/or iron oxides, mica based pigments, natural food colors anddyes suitable for food, drug and cosmetic applications, and mixturesthereof.

Additional Additives

i. Suspending Agents

The filaments of the present invention may further comprise a suspendingagent at concentrations effective for suspending water-insolublematerial in dispersed form in the compositions or for modifying theviscosity of the filament forming composition. Such concentrations ofsuspending agents range from about 0.1% to about 10% and/or from about0.3% to about 5.0% by weight on a dry filament basis.

Non-limiting examples of suitable suspending agents include anionicpolymers and nonionic polymers (e.g., vinyl polymers, acyl derivatives,long chain amine oxides, and mixtures thereof, alkanol amides of fattyacids, long chain esters of long chain alkanol amides, glyceryl esters,primary amines having a fatty alkyl moiety having at least about 16carbon atoms, secondary amines having two fatty alkyl moieties eachhaving at least about 12 carbon atoms). Examples of suspending agentsare described in U.S. Pat. No. 4,741,855.

ii. Other Additives

The filament and/or web of the present invention can include one or moreexcipients. Non-limiting examples of excipients can include non-watersoluble filament-forming materials or non-water soluble filaments,aesthetic agents, chelants, preservatives, UV absorbers, solid or otherliquid fillers, colliodal silica, probiotics, deposition aids, BHT,pearlescent agents, effervescent agents, color change systems,opacifiers, vitamins and amino acids such as: water soluble vitamins andtheir derivatives, water soluble amino acids and their salts and/orderivatives, water insoluble amino acids, viscosity modifiers, dyes,nonvolatile solvents or diluents (water soluble and insoluble),pearlescent aids, foam boosters, preservatives, heat transfer agents,proteins, sunscreens, niacinamide, or combinations thereof. In oneexample, the filaments of the present invention may comprise processingaids and/or materials that provide a signal (visual, audible, smell,feel, taste) that identifies when one or more of the active agentswithin the filament, web or shaving aid has been released from thefilament. Suitable non-water soluble filament forming materials andfilaments include for example polyamides and polyesters and mixturesthereof. In one embodiment the filament and or shaving aid aresubstantially free of said non-water soluble polymers.

Filament-forming Composition

The filaments of the present invention are made from a filament-formingcomposition. The filament-forming composition is a polar-solvent-basedcomposition. In one example, the filament-forming composition is anaqueous composition comprising one or more filament-forming materialsand optionally one or more additives and or active agents. The filamentforming materials are preferably water soluble materials.

The filament-forming composition of the present invention may have ashear viscosity as measured according to the Shear Viscosity Test Methoddescribed herein of from about 1 Pascal·Seconds to about 25Pascal·Seconds and/or from about 2 Pascal·Seconds to about 20Pascal·Seconds and/or from about 3 Pascal·Seconds to about 10Pascal·Seconds, as measured at a shear rate of 3,000 sec⁻¹ and at theprocessing temperature (50° C. to 100° C.).

The filament-forming composition may be processed at a temperature offrom about 50° C. to about 100° C. and/or from about 65° C. to about 95°C. and/or from about 70° C. to about 90° C. when making filaments fromthe filament-forming composition.

In one example, the filament-forming composition may comprise at least20% and/or at least 30% and/or at least 40% and/or at least 45% and/orat least 50% to about 90% and/or to about 85% and/or to about 80% and/orto about 75% by weight of one or more filament-forming materials, one ormore additives, and mixtures thereof. The filament-forming compositionmay comprise from about 10% to about 80% by weight of a polar solvent,such as water.

The filament-forming composition may exhibit a Capillary Number of atleast 1 and/or at least 3 and/or at least 5 such that thefilament-forming composition can be effectively polymer processed into ahydroxyl polymer fiber.

The Capillary number is a dimensionless number used to characterize thelikelihood of this droplet breakup. A larger capillary number indicatesgreater fluid stability upon exiting the die. The Capillary number isdefined as follows:

${Ca} = \frac{V*\eta}{\sigma}$

V is the fluid velocity at the die exit (units of Length per Time),

η is the fluid viscosity at the conditions of the die (units of Mass perLength*Time),

σ is the surface tension of the fluid (units of mass per Time²). Whenvelocity, viscosity, and surface tension are expressed in a set ofconsistent units, the resulting Capillary number will have no units ofits own; the individual units will cancel out.

The Capillary number is defined for the conditions at the exit of thedie. The fluid velocity is the average velocity of the fluid passingthrough the die opening. The average velocity is defined as follows:

$V = \frac{{Vol}^{\prime}}{Area}$

Vol′=volumetric flowrate (units of Length′ per Time),

Area=cross-sectional area of the die exit (units of Length²).

When the die opening is a circular hole, then the fluid velocity can bedefined as

$V = \frac{{Vol}^{\prime}}{\pi*R^{2}}$

R is the radius of the circular hole (units of length).

The fluid viscosity will depend on the temperature and may depend of theshear rate. The definition of a shear thinning fluid includes adependence on the shear rate. The surface tension will depend on themakeup of the fluid and the temperature of the fluid.

In a filament spinning process, the filaments need to have initialstability as they leave the die. The Capillary number is used tocharacterize this initial stability criterion. At the conditions of thedie, the Capillary number should be greater than 1 and/or greater than4.

In one example, the filament-forming composition exhibits a CapillaryNumber of from at least 1 to about 50 and/or at least 3 to about 50and/or at least 5 to about 30. The filament-forming composition of thepresent invention may have a shear viscosity of from about 1Pascal·Seconds to about 25 Pascal·Seconds and/or from about 2Pascal·Seconds to about 20 Pascal·Seconds and/or from about 3Pascal·Seconds to about 10 Pascal·Seconds, as measured at a shear rateof 3,000 sec⁻¹ and at the processing temperature (50° C. to 100° C.).

The filament-forming composition may be processed at a temperature offrom about 50° C. to about 100° C. and/or from about 65° C. to about 95°C. and/or from about 70° C. to about 90° C. when making fibers from thefilament-forming composition.

In one example, the non-volatile components of the spinning compositionmay comprise from about 20% and/or 30% and/or 40% and/or 45% and/or 50%to about 75% and/or 80% and/or 85% and/or 90%. The non-volatilecomponents may be composed of filament-forming materials, such asbackbone polymers, actives and combinations thereof. The volatilecomponent of the spinning composition will comprise the remainingpercentage and range from 10% to 80%.

The filament-forming composition may exhibit a Capillary Number of atleast 1 and/or at least 3 and/or at least 5 such that thefilament-forming composition can be effectively polymer processed into ahydroxyl polymer fiber.

The Capillary number is a dimensionless number used to characterize thelikelihood of this droplet breakup. A larger capillary number indicatesgreater fluid stability upon exiting the die. The Capillary number isdefined as follows:

${Ca} = \frac{V*\eta}{\sigma}$

V is the fluid velocity at the die exit (units of Length per Time),

η is the fluid viscosity at the conditions of the die (units of Mass perLength*Time),

σ is the surface tension of the fluid (units of mass per Time²). Whenvelocity, viscosity, and surface tension are expressed in a set ofconsistent units, the resulting Capillary number will have no units ofits own; the individual units will cancel out.

The Capillary number is defined for the conditions at the exit of thedie. The fluid velocity is the average velocity of the fluid passingthrough the die opening. The average velocity is defined as follows:

$V = \frac{{Vol}^{\prime}}{Area}$

Vol′=volumetric flowrate (units of Length³ per Time),

Area=cross-sectional area of the die exit (units of Length²).

When the die opening is a circular hole, then the fluid velocity can bedefined as

R is the radius of the circular hole (units of length).

The fluid viscosity will depend on the temperature and may depend of theshear rate. The definition of a shear thinning fluid includes adependence on the shear rate. The surface tension will depend on themakeup of the fluid and the temperature of the fluid.

In a filament spinning process, the filaments need to have initialstability as they leave the die. The Capillary number is used tocharacterize this initial stability criterion. At the conditions of thedie, the Capillary number should be greater than 1 and/or greater than4.

In one example, the filament-forming composition exhibits a CapillaryNumber of from at least 1 to about 50 and/or at least 3 to about 50and/or at least 5 to about 30.

In one example, the filament-forming composition may comprise one ormore antiblocking and/or detackifying agents. Non-limiting examples ofsuitable antiblocking and/or detackifying agents include starches,modified starches, crosslinked polyvinylpyrrolidone, crosslinkedcellulose, microcrystalline cellulose, silica, metalic oxides, calciumcarbonate, talc and mica.

Additives and or active agents of the present invention may be added tothe filament-forming composition prior to and/or during filamentformation and/or may be added to the filament after filament formation.For example, a perfume active agent may be applied to the filamentand/or web comprising the filament after the filament and/or webaccording to the present invention are formed. In another example,additives or active agents, which may not be suitable for passingthrough the spinning process for making the filament, may be applied tothe filament and/or web comprising the filament after the filamentand/or web according to the present invention by any suitable methodsincluding coating as discussed herein are formed.

Web

One or more, and/or a plurality of water soluble filaments of thepresent invention may form a web such as a nonwoven web by any suitableprocess known in the art. The web may be used as a form to deliver thewater-soluble filament forming materials preferably lubricating filamentforming materials and optionally the skin care active agents from thefilaments of the present invention when the web is exposed to conditionsof intended use of the filaments and/or nonwoven web i.e. shaving. Thewebs may have a basis weight of from about 40 gsm to about 250 gsm.

Even though the filament and/or web of the present invention are insolid form, the filament-forming composition used to make the filamentsof the present invention may be in the form of a liquid.

In one example, the web comprises a plurality of identical orsubstantially identical, from a compositional perspective, water solublefilaments. The web may also comprise two or more different filamentsaccording to the present invention. Non-limiting examples of differencesin the filaments may be physical differences such as differences indiameter, length, texture, shape, rigidness, elasticity, and the like;chemical differences such as crosslinking level, water solubility,melting point, Tg, active agent, filament-forming material, color, levelof active agent, level of filament-forming lubricating material,presence of any coating on filament, and the like; differences inwhether the filament loses its physical structure when the filament isexposed to conditions of intended use; differences in whether thefilament's morphology changes when the filament is exposed to conditionsof intended use; and differences in rate at which the filament dissolveswhen exposed to conditions of intended use. Two or more filaments withinthe web may comprise the same filament-forming material, but havedifferent active agents. For example, this may be the case where thedifferent active agents may be incompatible with one another. The webmay optionally also comprise one or more non-water soluble filaments.

The web may be provided as a single layer or may comprise at least twolayers, preferably a plurality of layers. Each layer of the web may bedifferent or identical in terms of physical or chemical properties asdiscussed hereinabove. In one embodiment, the web may comprise from 2 to12 layers produced using individual webs with a basis weight of from 40to 190 gsm. The layers are typically superimposed upon one another to aform a stack.

In one example, the single layer web of the present invention exhibits athickness of greater than 0.01 mm and/or greater than 0.05 mm and/orgreater than 0.1 mm and/or to about 20 mm and/or to about 10 mm and/orto about 5 mm and/or to about 2 mm and/or to about 0.5 mm and/or toabout 0.3 mm as measured by the Thickness Tes Method described herein.The layers and or webs preferably each have a uniform thickness.

The filaments of the invention and the webs formed therefrom may beselected to obtain a desirable rate of dissolution of the filaments orwebs in the conditions of intended use. In particular, the use ofmultiple layered webs enables the rate of dissolution to be controlledparticularly during multiple shaving events thereby ensuring thatsufficient lubricant and or skin actives are delivered during eachshaving event whilst ensuring the structural integrity of the web andpreventing premature depletion of the web. Multi-layered webs can alsoprovide a consumer desirable attribute delivering a soft and conformableshaving aid.

In one example, each individual layer of the web (in the absence of anycoating) of the present invention exhibits an average dissolution timeper g of sample of less than 120 and/or less than 100 and/or less than80 and/or less than 55 and/or less than 50 and/or less than 40 and/orless than 30 and/or less than 20 seconds/gram (s/g) as measuredaccording to the Dissolution Test Method described herein.

In another example, the web of the present invention comprising aplurality of layers (in the absence of any coating) exhibits an averagedissolution time per g of sample of less than 5000, and or less than4000 and/or less than 3500 seconds/gram s/g as measured according to theDissolution Test Method described herein.

The web may comprise at least 30% by weight of filaments of watersoluble filaments, or at least 40% or at least 50% or at least 50% or atleast 60% or at least 70% or at least 80% or at least 90% by weight ofwater soluble filaments.

Impregnated/Coated Web

The web of the present invention may be further coated with one or moreadditives such as skin care active agents by any means known in the art,including but not limited to spray coating, dip coating, printing and/orslot coating in addition to or in the absence of any coating ofindividual filaments. Preferably spray coating is employed to create awell-controlled distribution of the additive such as the skin careactive agent over the surface of the web. Preferably the active isuniformly applied and has the required characteristics to enable theadditive to wick into the web and thereby not remain solely on thesurface of the web. This may be facilitated by the addition of activesto reduce surface tension or by applying the skin care active agent atelevated temperatures so as to reduce its viscosity.

The coating may be uniformly applied over substantially the entire theupper skin facing surface and or lower surface of the web or may beapplied in a continuous or discontinuous pattern. If multiple layers ofwebs are used, then all or at least one of the surfaces of one of theweb layers may be coated with an additive in continuous or discontinuouspatterns. This may further facilitate the provision of a desirable rateof dissolution of the web over multiple usage events.

The coating may be a liquid or paste at ambient conditions or it may bea solid with a melting point of 40-90° C., even more preferably between40-60° C. The coating may be homogeneous or it may contain a dispersedparticulate phase.

The coating may comprise hydrophilic or hydrophobic skin care activeagent. The coating preferably comprises a hydrophobic skin care activeagent. This provides the benefit of treating the skin and controllingthe rate of dissolution of the web particularly during multiple shavingevents thereby ensuring that sufficient lubricant and or skin activesare delivered during each shaving event whilst ensuring the structuralintegrity of the web and preventing premature depletion of the web andskin active agents. Preferably the coating may comprise materialsselected from petrolatum, PDMS, polyethylene oxide, a wax or mixturesthereof. In one example the coating is comprised of at least 90%,preferably 100% petrolatum. The amount of coating applied to the web isfrom 4:1 to 1:8 (web:coating) weight ratio.

In one example, the coated single layer web of the present inventionexhibits an average dissolution time per g of sample of less than 120and/or less than 100 and/or less than 80 and/or less than 55 and/or lessthan 50 and/or less than 40 and/or less than 30 and/or less than 20seconds/gram (s/g) as measured according to the Dissolution Test Methoddescribed herein.

In another example, the coated multi-layer web of the present inventionexhibits an average dissolution time per g of sample of less than 1500and/or less than 1400 and/or less than 1300 and/or less than 1200seconds/gram s/g as measured according to the Dissolution Test Methoddescribed herein.

Bonded/Laminated Web

In one embodiment the web may comprise from at least two to about 20layers, preferably from 2 to 15 layers, even more preferably from 5 to12 layers. The number of layers required may depend upon the basisweight of each individual web. In order to ensure the integrity of themultilayer web, such multilayer webs may be bonded to form a laminateusing for example stacking and compression and or bonding techniqueswhereby the layers of web are superimposed and bonded together to form alaminate. The compression or bonding techniques include but are notlimited to the application of heat, pressure, ultrasound and/or water ora combination thereof.

In one embodiment, the multiple layered web may be formed into a parentroll, which may be subsequently unwound and molded into the desiredshape as discussed below or using a similar molding operation.

Multiple layered laminated webs may be formed by superimposing thelayers of the web, preferably coated layers, within a mould or form thatpreferably has the desired shape and size for the razor article forwhich it is to be employed. The layers of the web maybe cut to sizeprior to insertion within the mold or this may be achieved during thelamination step itself. In a preferred embodiment, the resultantlaminate web is bonded at least at the outer peripheral edges of the webor the desired in use shape and size. In this manner, the web retainsboth structural integrity and conformability when in planar view. Theresulting laminate therefore has lower density in the center of thelaminate than at the ‘sealed’ or bonded peripheral edges. The conditionsfor creating this laminate are selected dependent on the filamentforming materials, web formation and the nature of the coating employed.In an alternative embodiment, the layers of web are bonded together overat least a portion of the surface of the web, preferably substantiallythe entire the surface of the web. The bonding may be in a continuous ordiscontinuous pattern. The lamination of the web provides structuralintegrity thereto and may be utilized to control the rate of dissolutionthereof in use.

In one embodiment the shaving aid may also comprise a web formed ofnano-filaments. The web can be a single layer or can be multiple layers.In one embodiment, the shaving aid comprises a conventionally extrudedor molded water soluble shaving aid and/or a fibrous substratecomprising a filament is accompanied with the nano-filament web coatingat least a portion of the shaving aid that touches the skin during anormal shaving stroke. In another embodiment, more than onenano-filament web is applied onto the shaving aid. Without intending tobe bound by theory, it is believed that adding the one or morenano-filament webs can provide increased lubrication during the initialuses of the shaving aid as the nano-filaments can be selected todissolve within the first shave thereby releasing an initial burst oflubricants. Where co-axial nano-filaments are used, such as thosecomprising a silicone or other skin care active in the core, the shavingaid can also provide skin care benefits during the initial shave due tothe quick dissolving and breakdown of the co-axial nano-filaments.Mixtures of nano-fibers and co-axial nano-filaments can also be used,for example in one embodiment, the shaving aid comprises a nano-filamentweb and a second web made up of co-axial nano-filaments.

While it is possible to form a shaving aid comprising webs of filaments,the nano-filaments would likely be used as a web or plurality oflaminated webs coating at least a portion of the shaving aid. In oneembodiment, the shaving aid comprises from about 0.01% to 30% by weight,of said nano-filament, co-axial nano-filaments, or a combinationthereof, or from about 0.1% to about 5%, or from about 1% to about 3%.

In one embodiment, at least one of the nano-filaments forming the webhas a span of at least 30 μm between intersections with othernano-filaments in the shaving aid. The span can be from 10 μm to about100 μm. In one embodiment, the nano-filament web has a thickness of fromabout 0.01 mm to about 5 mm. In one embodiment, the shaving aidcomprises a plurality of such webs. In one embodiment, at least aportion of said skin contacting portion has a surface coating, saidsurface coating comprising said nano-filament, preferably wherein atleast 20%, or at least 50%, up to 80% or up to 100% of the skincontacting portion, by surface area is covered by said surface coating.In one embodiment, the surface coating has a thickness of from about0.01 mm to about 20 mm.

Hair Removal Head

According to the embodiments, the filaments find particular applicationfor hair removal devices. In one example, the filaments are located onthe housing of a hair removal device such as a razor cartridge or on ashaving aid therefore.

Hair removal devices generally comprise a hair removal head and a handleor grip portion, upon which the hair removal head is mounted. The hairremoval device can be manual or power driven and can be used for wetand/or dry applications. The hair removal head can include a widescraping surface such as where the hair removal device is used with adepilatory, or be a razor cartridge or foil where the device is ashaving razor. The hair removal head may be replaceable and/or pivotallyconnected to a cartridge connecting structure and in turn orindependently (e.g. permanently fixed) to a handle. In some embodiments,the cartridge connecting structure includes at least one arm toreleasably engage the hair removal head.

The hair removal head typically comprises one or more elongated edgesusually positioned between a first and second end, said one or moreelongated edges comprising a tip extending towards said first end. Wherethe hair removal head is a razor cartridge the one or more elongatededges can include blades. Such embodiments typically comprise a housingand blades contained therein.

The filament or web thereof may be located on at least a portion of thehousing for example on the skin contacting surface thereof and or may beprovided on the surface of or integral with a shaving aid of either aconventional or filament formed nature. For example, U.S. Pat. No.7,168,173 generally describes a FUSION® razor that is commerciallyavailable from The Gillette Company and which includes a razor cartridgewith multiple blades. Additionally, the razor cartridge may include aguard as well as a skin engaging member. A variety of razor cartridgescan be used in accordance with the present invention. Non-limitingexamples of suitable razor cartridges, with and without fins, guards,and/or shave aids, include those marketed by The Gillette Company underthe FUSION®, VENUS® product lines as well as those disclosed in U.S.Pat. Nos. 7,197,825, 6,449,849, 6,442,839, 6,301,785, 6,298,558;6,161,288, and U.S. 2008/060201. Those of skill in the art willunderstand that the shaving aid defined herein can be used with anycurrently marketed system or disposable razor, including those having 2,3, 4 or 5 blades. In such a case, the hair removal device is a razor,the hair removal head is a razor cartridge and the one or more elongatededges are blades. Another example of a hair removal device is a scrapingtool for use with a hair removal composition, i.e. a depilatory.

In some embodiments, the shaving aid is located on the portion of thecartridge that contacts skin during the hair removal process, forwardand/or aft of the blades. A feature “forward” of the one or moreelongated edges, for example, is positioned so that the surface to betreated with by the hair removal device encounters the feature before itencounters the elongated edges. A feature “aft” of the elongated edge ispositioned so that the surface to be treated by the hair removal deviceencounters the feature after it encounters the elongated edges. Wheremore than one shaving aid is provided on the hair removal device, theycan be the same (identical) or different, in terms of physicalshape/structure and/or chemical composition.

In some particular embodiments, a plurality (e.g. 2, a first and second)of shaving aids may be provided on the hair removal head, with the firstshaving aid comprising the same composition or different. These shavingaids may be placed collectively (for example adjacent to one another)ahead of or behind the elongated edges (e.g. blades on a razorcartridge), including side by side, or separately with one ahead of theelongated edges and the other behind.

In another embodiment at least a portion of the shaving aid may not belinear for example angled or curvilinear. Curvilinear as defined hereinmeans that at least a portion is curved such that it does not form astraight line. Where at least two shaving aids are provided, they canalso be positioned relative to one another such that they do not form astraight line.

In some embodiments, the curved or angled nature of the shaving aid issuch that it forms at least a partial ring. A partial ring, as definedherein, means that the structure has at least two curved or angledsections which are concave to form an inner region. The partial ring canalso include a curved or angled portion which is positioned convex tosaid inner region. One or more of said shaving aids may also bepositioned relative to one another to form a full ring. The ring can beformed by a single shaving aid but two or more can be touching at orabout their terminal ends, or even overlapping, to form such a ring.

The shaving aids may be free standing utilizing a suitable attachmentmeans such as adhesive, use of mechanical retention features or may becontained at least partially within a container. For embodimentscomprising more than one shaving aid, the filaments of the presentinvention may be present on one or more of the shaving aids present orall of the shaving aids or none of the shaving aids.

The hair removal head may comprise a conventional shaving aid comprisinga lubricant such as water soluble polymer typically intended to providelubrication in-use in a non-filament form. Examples of water solublepolymers include polyethylene oxide, polyvinyl pyrrolidone,polyacrylamide, polyhydroxymethacrylate, polyvinyl imidazoline,polyethylene glycol, polyvinyl alcohol, polyhydroxyethymethacrylate,silicone polymers, and a mixture thereof. In some embodiments, saidwater soluble polymer is selected from the group consisting of polyvinyl alcohol, polyethylene oxide, copolymers of polyethylene andpolypropylene oxide, polyethylene glycol, and mixtures thereof.

The water-soluble polymer will preferably comprise at least about 50%,more preferably at least about 60%, by weight of the shaving aid, up toabout 99%, (or up to about 90% of the lubricating material). Forexample, the water-soluble polymer may be present at an amount of atleast about 50%, preferably from about 50% to about 99.9%, morepreferably from about 60% to about 95% (e.g. from about 90% to about95%) and even more preferably from about 70% to about 90% by weight ofthe lubricating material. The more preferred water soluble polymers arethe polyethylene oxides generally known as POLYOX′ (available from UnionCarbide Corporation) or ALKOX® (available from Meisei Chemical Works,Kyoto, Japan). The water-soluble polymer, (especially these polyethyleneoxides), will preferably have average molecular weights of at leastabout 20,000, at least about 50,000, at least about 100,000 or fromabout 100,000 to 6 million, preferably about 00,000 to 5 million. Aparticularly preferred polyethylene oxide comprises a blend of about 40%to 80% of polyethylene oxide having an average mol. wt. of about 5million (e.g. POLYOX COAGULANT) and about 60% to 20% of polyethyleneoxide having an average mol. wt. of about 300,000 (e.g. POLYOXWSR-N-750). The polyethylene oxide blend may also advantageously containup to about 10% (for example about 5%) by weight of a low mol. wt. (i.e.MW<10,000) polyethylene glycol such as PEG-100.

The conventional shaving aid may further comprise a water-insolublepolymer, e.g. in which the water-soluble polymer is dispersed, which maybe referred to as a water-insoluble matrix. Preferably, the waterinsoluble polymer is present at a level of from about 0% to about 50%,more preferably about 5% to about 40%, and even more preferably about15% to about 35% by weight of the shaving aid member. Suitablewater-insoluble polymers which can be used include polyethylene (PE),polypropylene, polystyrene (PS), butadiene-styrene copolymer (e.g.medium and high impact polystyrene), polyacetal,acrylonitrile-butadiene-styrene copolymer, ethylene vinyl acetatecopolymer, polyurethane, and blends thereof such aspolypropylene/polystyrene blend or polystyrene/impact polystyrene blend.One preferred water-insoluble polymer is polystyrene, preferably ageneral purpose polystyrene, such as NOVA C2345A, or a high impactpolystyrene (HIPS) (i.e. polystyrene-butadiene), such as BASF 495F KG21.The strip or any portion should contain a sufficient quantity ofwater-insoluble polymer to provide adequate mechanical strength, bothduring production and use. In some embodiments, the shaving aidcomprises any other ingredients commonly found in commercially availableshaving aid members, such as those used on razor cartridges byGILLETTE®, SCHICK® or BIC®. Non-limiting examples of such shaving aidmembers include those disclosed in U.S. Pat. Nos. 6,301,785, 6,442,839,6,298,558, 6,302,785, and U.S. Patent Pubs 2008/060201, and2009/0223057.

The conventional shaving aids may be fabricated by any appropriatemethod, including injection molding, pressing, impregnation,spray-coating, calendaring and extrusion, the latter being preferred.All of the components of the aid can be blended prior to molding orextrusion. For best results, it is preferred that the components aredry. In summary, the method comprises the steps of providing a feedcomprising a water-soluble polymer, water insoluble polymer; preferablyheating said feed to a temperature of from 120° C. to 200° C., andmolding, pressing, impregnating, spray-coating, calendaring and/orextruding said feed to form a shaving aid member. The filament(s) orweb(s) of the invention may be located on the skin contacting surface ofsuch a conventional shaving aid and attached thereto using any meansknown in the art.

Method for Making the Filament, Web and or Shaving Aid

The filaments of the present invention may be made by any suitableprocess. A non-limiting example of a suitable process for making thefilaments is described below.

In one example, a method for making a filament according to the presentinvention comprises the steps of:

a. providing a filament-forming composition preferably comprising one ormore water soluble filament-forming materials and optionally one or moreadditives and or skin care active agents; and

b. spinning the filament-forming composition into one or more filaments

During the spinning step, any volatile solvent, preferably water,present in the filament-forming composition is removed, such as bydrying, as the filament is formed. In one example, greater than 50%and/or greater than 70% and/or greater than 90% of the weight of thefilament-forming composition's volatile solvent, such as water, isremoved during the spinning step, such as by drying the filament beingproduced.

The filament-forming composition is spun into one or more filaments byany suitable spinning process, such as electro-spinning, meltblowingand/or spinbonding. In one example, the filament-forming composition isspun into a plurality of filaments by meltblowing. For example, thefilament-forming composition may be pumped from an extruder to ameltblown spinnerette. Upon exiting one or more of the filament-formingholes in the spinnerette, the filament-forming composition is attenuatedwith air to create one or more filaments. The filaments may then bedried to remove any remaining solvent used for spinning, such as thewater. In another example, the filament forming composition is spun intoa plurality of filaments utilizing electrospinning techniques known inthe art. The filament forming composition is pumped from the makingvessel to an electrospinning tip wherein a charge is applied. Thefilament is attenuated in air during attraction towards the receivingdrum or belt. The filaments can be removed from the belt and applied tothe hair removal head by any means known in the art. Alternatively abase substrate or shaving aid component or components can be attached tothe receiving drum and the filaments form a coating on the upper surfaceof the shaving aid.

Methods of Making Nano-Filament Webs

In one embodiment, where the shaving aid comprises a nano-filament web,the nano-filament can be formed by electrospinning techniques such asthose disclosed in US2014/0277572, U.S. Pat. No. 7,390,760, andWO2001051690.

As used herein, the term “electrospinning” refers to a technology whichcan be used to produce nano-sized fibers referred to as electrospunfibers from a solution using interactions between fluid dynamics andcharged surfaces. Additionally, those of skill in the art willunderstand that electrospinning can also be used to create largerdiameter fibers such as those where the diameter is greater than 1 nm(which can be used to create filaments). In general, formation of theelectrospun fiber involves providing a solution to an orifice in a bodyin electric communication with a voltage source, wherein electric forcesassist in forming fine fibers that are deposited on a surface that maybe grounded or otherwise at a lower voltage than the body. Inelectrospinning, a polymer solution or melt provided from one or moreneedles, slots or other orifices is charged to a high voltage relativeto a collection grid. Electrical forces overcome surface tension andcause a fine jet of the polymer solution or melt to move towards thegrounded or oppositely charged collection grid. The jet can splay intoeven finer fiber streams before reaching the target and is collected asan interconnected web of small fibers. Specifically, as the solvent isevaporating (in processes using a solvent), this liquid jet is stretchedto many times it original length to produce continuous, ultrathin fibersof the polymer. The dried or solidified fibers can have diameters ofabout 40 nm, or from about 10 to about 100 nm, although 100 to 500 nmfibers are commonly observed. Various forms of electrospun nanofibersinclude branched nanofibers, tubes, ribbons and split nanofibers,nanofiber yarns, surface-coated nanofibers (e.g., with carbon, metals,etc.), nanofibers produced in a vacuum, and so forth. The production ofelectrospun fibers is illustrated in many publication and patents,including, for example, P. W. Gibson et al, “Electrospun Fiber Mats:Transport Properties,” AIChE Journal, 45(1): 190-195 (January 1999),which is hereby incorporated herein by reference.

In one embodiment of the present invention, the method of making ashaving aid comprising: extruding a shaving aid through a die to form anextruded shaving aid, said shaving aid having a skin contacting surface;and electrospinning a nano-filament onto a portion of the skincontacting surface to form a coated shaving aid. In one embodiment, saidextruded shaving aid is allowed to cool (such as to 25 C°) and/or hardenbefore the step of electrospinning. In another embodiment, the methodfurther comprises a step of cutting a portion of said coated shaving aidto form a prepared shaving aid. In one embodiment, multiple layers ofthe web are used, the web can be formed, then folded before beingapplied over a portion of the shaving aid.

Coating Filaments with Additives

The filaments of the present invention may be coated with additives oractive agents by any means known in the art, but not limited to spraycoating, printing, dip coating or combinations thereof.

Formation of the Web

The filaments of the present invention may be collected on a belt, suchas a patterned belt to form a web comprising the filaments. Non-watersoluble filaments may also be fed onto the belt to form a web comprisingboth water soluble and non-water soluble filaments.

In one embodiment, the web may be coated with an additive and or skincare active by any means known in the art, including but not limited tospray coating, dip coating, printing and/or slot coating. Preferablyspray coating is employed. In one non-limiting example, the coating isapplied using an X-Y table to create a well-controlled distribution ofthe additive such as the skin care active agent over at least onesurface of the web.

In another embodiment, at least two layers of the web (coated oruncoated) are bonded to form a laminate by any means known in the art.Typically, this may be achieved by utilization of a mould to form thedesired shape and size such as a shaving aid and the addition of heat,pressure and water or combinations thereof. In one example, the coatedweb layers are bonded using a combination of heat, pressure and waterapplied to the web. The water used may be present as steam or morepreferably may be applied to the web as a fine spray. In anotherexample, the coating used is thermo-setting and heat and pressure onlyare used.

Methods of Use

The filament and webs optionally comprising one or more skin care activeagents according to the present invention may be utilized in a methodfor treating skin during the shaving process. The method of treating theskin may comprise one or more steps including (a) attaching the filamentor web or shaving aid thereof to the razor or to the housing or to theshaving aid; (b) contacting the razor with water; (c) contacting therazor with the skin and moving across the skin in a manner consistentwith removing the hair; (d) rinsing and drying and the skin; and (e)combinations thereof.

NON-LIMITING EXAMPLES Example 1-10: Water Soluble Filaments

Examples 1-10 are produced by using a small-scale apparatus comprising apressurized tank suitable for batch operations is filled with afilament-forming composition, for example a filament-forming compositionthat is suitable for making filaments useful as articles for razors. Thesteps for making the filament forming composition comprise;

-   -   i) Disperse the lubricating materials in water (temp) and mix        with mechanical agitation (speed). The materials can be mixed        together or can be made into separate pre-mixes and then        combined.    -   ii) Add any additional ingredients such as additives or skin        care active agents.    -   iii) If necessary heat to 90° C. and continue to mix to form a        uniform dispersion of the lubricating materials and any        additional materials.    -   iv) Use above filament forming composition to spin into        filaments

A pump (for example a Zenith, type PEP II pump having a capacity of 5.0cubic centimeters per revolution (cc/rev, manufactured by ParkerHannifin Corporation, Zenith Pumps division, of Sanford, N.C., USA) isused to pump the filament-forming composition to a die. Thefilament-forming composition's material flow to a die is controlled byadjusting the number of revolutions per minute (rpm) of the pump. Pipesare connected the tank, the pump, and the die in order to transport thefilament-forming composition from the tank to the pump and into the die.The die has two or more rows of circular extrusion nozzles spaced fromone another at a pitch of about 1.524 millimeters (about 0.060 inches).The nozzles have individual inner diameters of about 0.305 millimeters(about 0.012 inches) and individual outside diameters of about 0.813millimeters (about 0.032 inches). Each individual nozzle is encircled byan annular and divergently flared orifice to supply attenuation air toeach individual nozzle. The filament-forming composition that isextruded through the nozzles is surrounded and attenuated by generallycylindrical, humidified air streams supplied through the orificesencircling the nozzles to produce the filaments. Attenuation air isprovided by heating compressed air from a source by anelectrical-resistance heater, for example, a heater manufactured byChromalox, Division of Emerson Electric, of Pittsburgh, Pa., USA. Anappropriate quantity of steam is added to the attenuation air tosaturate or nearly saturate the heated air at the conditions in theelectrically heated, thermostatically controlled delivery pipe.Condensate is removed in an electrically heated, thermostaticallycontrolled, separator. The filaments are dried by a drying air streamhaving a temperature of from about 149° C. (about 300° F.) to about 315°C. (about 600° F.) by an electrical resistance heater (not shown)supplied through drying nozzles (not shown) and discharged at an angleof about 90° relative to the general orientation of the filaments beingspun. The filaments may be collected on a collection device, such as abelt or fabric, in one example a belt or fabric capable of imparting apattern, for example a non-random repeating pattern to a nonwoven webformed as a result of collecting the filaments on the belt or fabric.The basis weight of the web was from 40 to 250 gsm.

Examples 11-14: Electrospun Water Soluble Filaments

Examples 11-14 are produced using a small scale electrospinningapparatus supplied by Spraybase, of Dublin, Ireland. Aqueous polymersolutions are prepared as described in examples 12-14. These solutionsare then drawn into syringes which are coupled by luer locks to flexiblePTFE tubing. The syringes are placed in a syringe pump supplied bySpraybase and the emitting end of the tubing is coupled to a metallic 20gauge emitter by a luer lock. The metal emitter is then placed on atranslating stage directly across from a rotating metal drum collector.The metal drum collector is covered with aluminum foil to allow easysample recovery and storage. The entire system is controlled by a PClinked by USB. A metal pin provides charge to the emitter while the drumis grounded. A voltage difference between the emitter and the drumcreates and electric field through which the polymer solutions arepumped at flow rates ranging from 0.4 mL/hr-0.8 mL/hr. The appliedvoltage ranges from 5 kV to 15 kV. The distance between the emitter tipand the collecting drum ranges from 15 cm to 30 cm. These processsettings are tuned for each formulation until a stable Taylor cone isobserved at the emitter tip as is familiar to anyone with skill in theart.

Specifically, for the coaxial fiber outlined in Example 11, anadditional syringe pump is used for a total of 2 syringe pumps. Aspecial coaxial emitter tip is used consisting of a 26 gauge needleconcentrically mounted inside a 20 gauge needle supplied by Spraybase.The outer (sheath) fluid is pumped into the 20 gauge needle space whilethe inner (core) hydrophobic liquid is pumped into the 26 gauge needlespace. The concentricity of the fluids is maintained as they enter theabove mentioned electric field and are drawn by electrohydrodynamicforces into small diameter fibers. In this way, a dry PEO sheathencapsulates a hydrophobic liquid core. The flow rate for the innerliquid is ideally 0.04 mL/hr and the flow rate for the outer liquid canbe 0.4 mL/hr.

Examples 1-5 Filaments

The Following Filament Forming Compositions were Prepared:—

Filament forming composition 1 2 3 % % % 4 5 w/w w/w w/w % w/w % w/wLubricating PVOH KL318* 12.50 0.00 12.50 12.50 12.50 Filament PVA 420H*0.00 15.00 0.00 0.00 0.00 Forming Polyox N750** 0.00 0.00 0.00 2.38 2.38Material Polyox N60K** 0.40 0.00 1.54 0.00 0.00 Polyox Coag** 0.00 0.550.00 0.23 0.23 Propylene Glycol{circumflex over ( )} 0.00 2.76 0.00 0.000.00 PEG 400{circumflex over ( )} 0.00 0.00 3.51 1.88 6.25 PG300{circumflex over ( )} 0.00 0.00 0.00 4.38 0.00 Skin Care Tween 800.00 0.00 0.00 0.00 2.50 Active Agent Solvent Water 87.10 81.69 82.4578.63 76.14 *PVOH KL 318 and PVA420H supplied by Kuraray. **Polyox N750,N60K and Coag supplied by Dow Chemical, {circumflex over ( )}PEG400 and300 supplied by BASF.

The Following Filament Compositions were Formed Therefrom

Filament composition 1 2 3 4 5 % w/w % w/w % w/w % w/w % w/w dry dry drydry dry filament filament filament filament filament Lubricating PVOH96.88 — 71.2  58.55 52.41 Filament KL318 Forming PVA — 81.92 — — —Material 420H Polyox — — — 11.12  9.96 N750 Polyox  3.12 —  8.76 — —N60K Polyox —  2.99 —  1.05  0.94 Coag Propylene — 15.08 — — — GlycolPEG — — 19.99  8.78 26.20 400 PEG — — — 20.49 — 300 Skin Care Tween 80 —— — — 10.48 Active Agent

Example Filaments 6-10

The Following Filament Forming Compositions were Prepared:—

Filament forming material 6 7 8 9 10 % w/w % w/w % w/w % w/w % w/wLubricating PVOH 12.5 15.00 — — 15.00 Filament KL318* Forming Polyox 2.52.5 — — 2.5 Material N750** Polyox 0.225 0.11 — — 0.11 Coag** PEG400{circumflex over ( )} 5.00 5.00 — — 5.00 Merquat — — 42 — — 280Merquat — — — 22 — 2001 Solvent Water 79.775 77.39 58 78 77.39

The Following Filaments were Formed Therefrom:—

Filament composition 6 7 8 9 10 % w/w % w/w % w/w % w/w % w/w dry drydry dry dry filament filament filament filament filament LubricatingPVOH 61.80 66.30 — — 83.3  Filament KL318 Forming Polyox 12.36 11.10 — —2.5 Material N750 Polyox  1.11  0.49 — — 0.1 Coag PEG 400 24.72 22.11 ——  5.00 Merquat — — 100.0 — — 280 Merquat — — — 100 — 2001

Examples 11-14

Filament forming 11 12 13 14 material % w/w % w/w % w/w % w/wLubricating Polyox N750 * 4 2 8 5 Filament Polyox Coag ** — — — —Forming PEG 400{circumflex over ( )} — — — — Material Polyox N60K 1 1 —1 Polyox N12K — 2 — — Pluronic F-127 1 1 2 1 Solvent Water 94  94  90 93 

The filaments exemplified below were produced from the filament formingcompositions above;

11 12 13 14 Filament % w/w dry % w/w % w/w % w/w composition web dry webdry web dry web Lubricating Polyox N750 25.6  33.33 80 71.43  FilamentPolyox Coag — — — — Forming PEG 400 — — — — Material Polyox N60K 6.4216.67 — 14.285 Polyox N12K — 33.33 — — Pluronic F- 6.42 16.67 20 14.285127 Additive DC200 200 cst 61.56  — — —

Coatings

As discussed herein above the individual layers of the web may becoated. This may be performed using a spray coating device. This caneither be manual with a controlled flow but uncontrolled deliveryconditions. Preferably a device such as an X-Y table is employed whichcontrols both the flow and the location of droplet delivery.Alternatively a spray gun may be employed using a flow rate in the rangeof 100-200 ml/min. The coating may be heated to improve flowabilitythrough the spray device.

The filaments or non-woven webs described in Examples 1-10 and 11-14above may be coated. Examples of suitable coatings comprising skin careactive agents are shown below.

A B C Coating % w/w % w/w % w/w Skin Care Petrolatum 100.0 15.23 —Active Silicone DC200 — 21.19 — Agent 350 cst $ Softcat SL5 * — 10.60 —Planell oil EU {circumflex over ( )} — — 16.25 Silwet L7210 + — 21.1935.0 Cetyl alcohol — 26.50 27.0 Multiwax 180MH # —  5.29 5.5Suppliers: * - Dow Chemicals, {circumflex over ( )} - Lonza, $ - DowCorning, # - Sonnenborn, + - Momentive

Coatings B and C were manufactured in sanitized equipment. The makingvessel is heated to 85° C. via a water bath or heating jacket and thelipophilic structurants are added (cetyl alcohol, Multiwax). The oilphase ingredients are then added and mixed until fully liquid. The heatis then reduced to 55° C. and the powder ingredients are added (SoftCat)and mixed until evenly dispersed. The mixture can then be cooled to roomtemperature and stored for coating or can be coated directly whilstmolten. If a thick coating layer is required then the coating can alsobe poured into an appropriate mould and cooled to form a separate solidpart.

Single layers of coated webs or filaments can be employed for use on therazor cartridge. One example of this is to coat a single layer of theweb produced in Example 6 above with 92 gsm of Coating A. Thiscombination has been tested in the dissolution test below and isdescribed as Example 6A (and depicted in FIG. 4).

Laminates

Multiple layers of the webs may be stacked together and compressed toform a laminate. The conditions required are dependent upon whether thelayers of the webs are coated or uncoated. Typically, the processrequires the positioning of the stacked webs within a mould suitable forforming the shaving aid and the application of heat, pressure andoptionally water or a thermo-setting material. According to the web andcoating, formulation compression times in the range 2-7 min atconditions of 50-120° C. and 1000-2500 kgf are employed. A cooling timeafter compression is preferred.

The following laminated webs were prepared as indicated below and aredepicted in FIGS. 1 to 4 (L1, L2, L3, 6, 6A, L6, L4 and L5).

1. Select filaments for laminate construction according to gsm of webrequired and type of coating to be employed. Coat the web or filamentswith the coating selected,

2. Define number of web layers to be used and cut to appropriate sizeand record mass. The mass of the total web stack should be recorded.

3. If multiple coatings are being employed then the second coating isapplied when the web stack is being assembled. It can be applied as asolid pre-formed sheet or by any known means such as slot coating on theweb required.

4. For coating type A with no thermo set material present in thecoating, a light application of water may be required to form thelaminate. A fine spray is employed to evenly and lightly coat each weblayer prior to stacking.

5. A suitable mould with cavities forming the parts suitable for laterattachment to the razor is provided. This mould can apply pressureevenly over the whole surface of the laminate or more typically localizethe pressure around the edge of the part to ensuring sealing.

6. The assembled web stack is then placed in the mould, and which isplaced in a suitable hydraulic press with heated platens to reach thetemperatures and pressures required. Typically, the mould is around12×12 cm2 in size to enable fitting into the press.

7. For coatings type B and C these will thermo set and form the laminateon heating and compression. A temperature of 50° C. for 2 mins at a loadof 2000-2500 kgf is utilized.

8. For coating type A, typical conditions are 120° C. applied for 7 minsat 800-1000 kgf. The amount of water used to adjoin the layers willinfluence these conditions.

9. Extract the mould from the press and allow to cool for at least 5mins with a weight on the mould to maintain a low pressure (typically 5kg).

10. Once cooled, the formed laminate is removed from the mould and cutto shape if required. The laminate may then be attached to the razorcartridge housing by adhesive or any other suitable means.

Laminate L1 L2 L3 L4 L5 L6 Web Example 6 Example 6 Example 6 Example 6Example 6 Example 6 Web basis weight 190 190 40 190 190  190 (gsm)Number of layers of  5  2 12  3  3   1 web Coating 1 A A C — A C Coatingbasis weight  50  65 40 —  92 1520 (gsm) Coating employed on Yes 2layers Yes — Yes Yes ll web layers Coating 2 — B — — — — Coating basisweight — 462 — — — — (gsm) Coating employed on — — — — — — all weblayers

Using the Dissolution test method described herein, the rate ofdissolution of the examples 6, 6A, L6, L4 and L5 is clearly shownbelow:—

Example 6 Example 6A Example L4 Example L5 1 Layer 1 Layer 3 Layers 3Layers N = 3 Uncoated (s/g) Coated (s/g) Uncoated (s/g) Coated (s/g)Mean 20.052 9.902 3293.450 1185.688 St. Er. 6.166 2.457 1512.277 162.951

As can be seen from the data above, formation of a laminated structuresignificantly increases dissolution time. This has the advantage ofincreasing the rate of dissolution and thereby controlling the rate atwhich the lubricating materials and or skin actives are delivered to theskin during the shaving process.

FIG. 5 shows a FESEM image of a nano-filament web in accordance with atleast one embodiment of the present invention. This sample comprises 5%by weight of PEO having MW=900 kDa. Nano-fibers are measured havingaverage diameter of about 337 nm.

-   -   Image analysis performed using Fiji (ImageJ)    -   Pixel ratio set by SEM scale bar    -   n=25 measurements taken per image, labeled, and reported

Test Methods

Unless otherwise indicated, all tests described herein including thosedescribed under the Definitions section and the following test methodsare conducted on samples that have been conditioned in a conditionedroom at a temperature of 73° F.±4° F. (about 23° C.±2.2° C.) and arelative humidity of 50%±10% for 2 hours prior to the test unlessotherwise indicated. Samples conditioned as described herein areconsidered dry samples (such as “dry filaments”) for purposes of thisinvention. Further, all tests are conducted in such conditioned room.

Water Content Test Method

The water (moisture) content present in a filament and/or web ismeasured using the following Water Content Test Method.

A filament and/or web or portion thereof (“sample”) is placed in aconditioned room at a temperature of 73° F.±4° F. (about 23° C.±2.2° C.)and a relative humidity of 50%±10% for at least 24 hours prior totesting. The weight of the sample is recorded when no further weightchange is detected for at least a 5 minute period. Record this weight asthe “equilibrium weight” of the sample. Next, place the sample in adrying oven for 24 hours at 70° C. with a relative humidity of about 4%to dry the sample. After the 24 hours of drying, immediately weigh thesample. Record this weight as the “dry weight” of the sample. The water(moisture) content of the sample is calculated as follows:

${\% \mspace{14mu} {Water}\mspace{14mu} ({moisture})\mspace{14mu} {in}\mspace{14mu} {sample}} = {100\% \times \frac{\left( {{{Equilibrium}\mspace{14mu} {weight}\mspace{14mu} {of}\mspace{14mu} {sample}} - {{Dry}\mspace{14mu} {weight}\mspace{14mu} {of}\mspace{14mu} {sample}}} \right)}{{Dry}\mspace{14mu} {weight}\mspace{14mu} {of}\mspace{14mu} {sample}}}$

The % Water (moisture) in sample for 3 replicates is averaged to givethe reported % Water (moisture) in sample.

Dissolution Test Method

Apparatus and Materials:

-   -   600 mL Beaker    -   Magnetic Stirrer (Labline Model No. 1250 or equivalent)    -   Magnetic Stirring Rod (5 cm)    -   Thermometer (1 to 100° C.+/−1° C.)    -   Template, Stainless Steel (3.8 cm×3.2 cm)    -   Timer (0-300 seconds, accurate to the nearest second)    -   35 mm Slide Mount having an open area of 3.8 cm×3.2 cm        (commercially available from Polaroid Corporation)    -   35 mm Slide Mount Holder    -   Tap Water or equivalent having the following properties: Total        Hardness=155 mg/L as CaCO3; Calcium content=33.2 mg/L; Magnesium        content=17.5 mg/L; Phosphate content=0.0462

Sample Preparation:

-   -   1. Cut 3 test samples from the web to be tested (“sample”) using        the template to ensure that the sample fits within the 35 mm        slide mount with open area dimensions 24×36 mm (i.e. 3.8 cm×3.2        cm specimen). Cut the samples from areas of the web equally        spaced along the transverse direction of the web.    -   2. Lock each of the 3 samples in a separate 35 mm slide mount.    -   3. Place magnetic stirring rod into the 600 mL Beaker.    -   4. Obtain 500 mL or greater of Cincinnati city water and measure        water temperature with thermometer and, if necessary, adjust the        temperature of the water to maintain it at the testing        temperature; namely, 5° C. Once the water temperature is at 5°        C., fill the 600 mL beaker with 500 mL of the water.    -   5. Next, place the beaker on the magnetic stirrer. Turn the        stirrer on, and adjust stir speed until a vortex develops in the        water and the bottom of the vortex is at the 400 mL mark on the        600 mL beaker.    -   6. Secure the 35 mm slide mount with sample locked therein in a        holder designed to lower the 35 mm slide mount into the water in        the beaker, for example an alligator clamp of a 35 mm slide        mount holder designed to position the 35 mm slide mount into the        water present in the 600 mL beaker. The 35 mm slide mount is        held by the alligator clamp in the middle of one long end of the        35 mm slide mount such that the long ends of the 35 mm slide        mount are parallel to the surface of the water present in the        600 mL beaker. This set up will position the film or nonwoven        surface perpendicular to the flow of the water. A slightly        modified example of an arrangement of a 35 mm slide mount and        slide mount holder are shown in FIGS. 1-3 of U.S. Pat. No.        6,787,512.    -   7. In one motion, the 35 mm slide mount holder, which positions        the 35 mm slide mount above the center of the water in the        beaker, is dropped resulting in the 35 mm slide mount becoming        submerged in the water sufficiently such that the water contacts        the entire exposed surface area of the film or nonwoven sample        locked in the 35 mm slide mount. As soon as the water contacts        the entire exposed surface area of the film or nonwoven start        the timer. Disintegration occurs when the film or nonwoven        breaks apart. When all of the visible web is released from the        slide mount, raise the 35 mm slide mount out of the water while        continuing to monitor the water for undissolved web fragments.        Dissolution occurs when all web fragments are no longer visible        in the water.    -   8. Three replicates of each sample are run.    -   9. Each disintegration and dissolution time is normalized by        weight of the sample to obtain values of the disintegration and        dissolution times per g of sample tested, which is in units of        seconds/gram of sample (s/g). The average disintegration and        dissolution times per g of sample tested of the three replicates        are recorded.

Diameter Test Method

The diameter of a discrete filament or a filament within a web isdetermined by using a Scanning Electron Microscope (SEM) or an OpticalMicroscope and image analysis software. A magnification of 200 to 10,000times is chosen such that the filaments are suitably enlarged formeasurement. When using the SEM, the samples are sputtered with gold ora palladium compound to avoid electric charging and vibrations of thefilament in the electron beam. A manual procedure for determining thefilament diameters is used from the image (on monitor screen) taken withthe SEM or the optical microscope. Using a mouse and a cursor tool, theedge of a randomly selected filament is sought and then measured acrossits width (i.e., perpendicular to filament direction at that point) tothe other edge of the filament. A scaled and calibrated image analysistool provides the scaling to get actual reading in μm. For filamentswithin a web, several filaments are randomly selected across the sampleof the web using the SEM or the optical microscope. At least twoportions the web (or web inside a product) are cut and tested in thismanner Altogether at least 100 such measurements are made and then alldata are recorded for statistical analysis. The recorded data are usedto calculate average (mean) of the filament diameters, standarddeviation of the filament diameters, and median of the filamentdiameters.

Another useful statistic is the calculation of the amount of thepopulation of filaments that is below a certain upper limit. Todetermine this statistic, the software is programmed to count how manyresults of the filament diameters are below an upper limit and thatcount (divided by total number of data and multiplied by 100%) isreported in percent as percent below the upper limit, such as percentbelow 1 micrometer diameter or %-submicron, for example. We denote themeasured diameter (in μm) of an individual circular filament as di.

In case the filaments have non-circular cross-sections, the measurementof the filament diameter is determined as and set equal to the hydraulicdiameter which is four times the cross-sectional area of the filamentdivided by the perimeter of the cross-section of the filament (outerperimeter in case of hollow filaments). The number-average diameter,alternatively average diameter is

${{calculated}\mspace{14mu} {as}\text{:}\mspace{14mu} d_{num}} = \frac{\sum\limits_{i = 1}^{n}d_{i}}{n}$

Thickness Method

Thickness of a web (single or multi-layer) is measured by cutting 5samples of a web sample such that each cut sample is larger in size thana load foot loading surface of a VIR Electronic Thickness Tester ModelII available from Thwing-Albert Instrument Company, Philadelphia, Pa.Typically, the load foot loading surface has a circular surface area ofabout 3.14 int. The sample is confined between a horizontal flat surfaceand the load foot loading surface. The load foot loading surface appliesa confining pressure to the sample of 15.5 g/cm². The caliper of eachsample is the resulting gap between the flat surface and the load footloading surface. The caliper is calculated as the average caliper of thefive samples. The result is reported in millimeters (mm).

Shear Viscosity Test Method

The shear viscosity of a filament-forming composition of the presentinvention is measured using a capillary rheometer, Goettfert Rheograph6000, manufactured by Goettfert USA of Rock Hill S.C., USA. Themeasurements are conducted using a capillary die having a diameter D of1.0 mm and a length L of 30 mm (i.e., /D=30). The die is attached to thelower end of the rheometer's 20 mm barrel, which is held at a die testtemperature of 75° C. A preheated to die test temperature, 60 g sampleof the filament-forming composition is loaded into the barrel section ofthe rheometer. Rid the sample of any entrapped air. Push the sample fromthe barrel through the capillary die at a set of chosen rates1,000-10,000 seconds⁻¹. An apparent shear viscosity can be calculatedwith the rheometer's software from the pressure drop the sampleexperiences as it goes from the barrel through the capillary die and theflow rate of the sample through the capillary die. The log (apparentshear viscosity) can be plotted against log (shear rate) and the plotcan be fitted by the power law, according to the formula η=Kγ^(n-1),wherein K is the material's viscosity constant, n is the material'sthinning index and γ is the shear rate. The reported apparent shearviscosity of the filament-forming composition herein is calculated froman interpolation to a shear rate of 3,000 sec⁻¹ using the power lawrelation.

Basis Weight Test Method

Basis weight of a single layer web is measured by selecting twelve (12)individual fibrous structure samples and making two stacks of sixindividual samples each. If the individual samples are connected to oneanother vie perforation lines, the perforation lines must be aligned onthe same side when stacking the individual samples. A precision cutteris used to cut each stack into exactly 3.5 in.×3.5 in. squares. The twostacks of cut squares are combined to make a basis weight pad of twelvesquares thick. The basis weight pad is then weighed on a top loadingbalance with a minimum resolution of 0.01 g. The top loading balancemust be protected from air drafts and other disturbances using a draftshield. Weights are recorded when the readings on the top loadingbalance become constant. The Basis Weight is calculated as follows:

${{Basis}\mspace{14mu} {Weight}} = \frac{{Weight}\mspace{14mu} {of}\mspace{14mu} {basis}\mspace{14mu} {weight}\mspace{14mu} {single}\mspace{14mu} {layer}\mspace{14mu} {{web}{\; \;}(g)} \times 10,000\mspace{14mu} {cm}^{2}\text{/}m^{2}}{79.0321\mspace{14mu} {cm}^{2}\mspace{11mu} \left( {{Area}\mspace{14mu} {of}\mspace{14mu} {basis}\mspace{14mu} {weight}\mspace{14mu} {pad}} \right) \times 12\mspace{14mu} {samples}}$

The dimensions and values disclosed herein are not to be understood asbeing strictly limited to the exact numerical values recited. Instead,unless otherwise specified, each such dimension is intended to mean boththe recited value and a functionally equivalent range surrounding thatvalue. For example, a dimension disclosed as “40 mm” is intended to mean“about 40 mm”

Every document cited herein, including any cross referenced or relatedpatent or application, is hereby incorporated herein by reference in itsentirety unless expressly excluded or otherwise limited. The citation ofany document is not an admission that it is prior art with respect toany invention disclosed or claimed herein or that it alone, or in anycombination with any other reference or references, teaches, suggests ordiscloses any such invention. Further, to the extent that any meaning ordefinition of a term in this document conflicts with any meaning ordefinition of the same term in a document incorporated by reference, themeaning or definition assigned to that term in this document shallgovern.

While particular examples and/or embodiments of the present inventionhave been illustrated and described, it would be obvious to thoseskilled in the art that various other changes and modifications can bemade without departing from the spirit and scope of the invention. It istherefore intended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A razor cartridge comprising a housing a shavingsurface; at least one blade having a blade tip positioned at saidshaving surface; and a shaving aid positioned on said housing to exposeskin contacting portion of said shaving aid on said shaving surface,said shaving aid comprising a co-axial filament having a diameter offrom about 10 nm to about 1000 nm, wherein said co-axial filamentcomprises a core and a sheath.
 2. The razor cartridge of claim 1,wherein said core comprises a water insoluble polymer.
 3. The razorcartridge of claim 1, wherein said sheath comprises a watersoluble-polymer.
 4. The razor cartridge of claim 2, wherein said sheathcomprises a water-soluble polymer.
 5. The razor cartridge of claim 1,wherein said core has a diameter of from about 90 nm to about 900 nm. 6.The razor cartridge of claim 1, wherein said sheath has a diameter offrom about 100 nm to 1000 nm.
 7. The razor cartridge of claim 1, whereinsaid co-axial filament has an average diameter of from about 300 nm toabout 600 nm.
 8. The razor cartridge of claim 1, further comprising asecond filament.
 9. The razor cartridge of claim 1, wherein said shavingaid comprises at least 0.01% by weight of a plurality of said co-axialfilaments.
 10. The razor cartridge of claim 1, wherein at least aportion of said skin contacting portion has a surface coating, saidsurface coating comprising said co-axial filament.
 11. The razorcartridge of claim 10, wherein at least 50% of the skin contactingportion, by surface area is covered by said surface coating.
 12. Therazor cartridge of claim 3, wherein said water soluble polymer isselected from polyvinylalcohol, quaternary ammonium polymer,polyethylene glycol, polyethyleneoxide, polypropylene oxide, or acombination thereof.
 13. The razor cartridge of claim 12, wherein thenano-filament comprises a copolymer of polyethylene oxide andpolypropylene oxide.
 14. The razor cartridge of claim 1, wherein saidco-axial filament comprises at least two components which areimmiscible.
 15. A method of making a shaving aid for use on a razorcomprising: a. extruding a shaving aid through a die to form an extrudedshaving aid, said shaving aid having a skin contacting surface; andelectrospinning at least two components to form a co-axial nano-filamentonto a portion of the skin contacting surface to form a coated shavingaid, said two components being immiscible.